notnull

GitOrigin-RevId: a62047f61869bc1971b700232adbde58019ad265

java/structuralsearch-java/src/com/intellij/structuralsearch/JavaPredefinedConfigurations.java

@@ -4,6 +4,7 @@ package com.intellij.structuralsearch;
 import com.intellij.ide.highlighter.JavaFileType;
 import com.intellij.openapi.fileTypes.StdFileTypes;
 import com.intellij.structuralsearch.plugin.ui.Configuration;
+import org.jetbrains.annotations.NotNull;
 
 import static com.intellij.structuralsearch.PredefinedConfigurationUtil.createSearchTemplateInfo;
 import static com.intellij.structuralsearch.PredefinedConfigurationUtil.createSearchTemplateInfoSimple;
@@ -12,6 +13,7 @@ import static com.intellij.structuralsearch.PredefinedConfigurationUtil.createSe
 * @author Bas Leijdekkers
 */
 final class JavaPredefinedConfigurations {
+  @NotNull
   public static Configuration[] createPredefinedTemplates() {
     return new Configuration[] {
       // Expression patterns

java/structuralsearch-java/src/com/intellij/structuralsearch/JavaReplaceHandler.java

@@ -359,7 +359,7 @@ public class JavaReplaceHandler extends StructuralReplaceHandler {
     }
     final List<? extends PsiElement> unmatchedAnnotations = originalModifierList.getUserData(GlobalMatchingVisitor.UNMATCHED_ELEMENTS_KEY);
     final PsiElement anchor = replacementModifierList.getFirstChild();
-    boolean append = (anchor == null);
+    boolean append = anchor == null;
     PsiElement child = originalModifierList.getFirstChild();
     while (child != null) {
       if (child instanceof PsiKeyword) {
@@ -417,7 +417,7 @@ public class JavaReplaceHandler extends StructuralReplaceHandler {
   }
 
   @Override
-  public void replace(final ReplacementInfo info, ReplaceOptions options) {
+  public void replace(final @NotNull ReplacementInfo info, @NotNull ReplaceOptions options) {
     final PsiElement elementToReplace = StructuralSearchUtil.getPresentableElement(info.getMatch(0));
     if (elementToReplace == null) {
       return;
@@ -689,7 +689,7 @@ public class JavaReplaceHandler extends StructuralReplaceHandler {
   }
 
   @Override
-  public void postProcess(PsiElement affectedElement, ReplaceOptions options) {
+  public void postProcess(@NotNull PsiElement affectedElement, @NotNull ReplaceOptions options) {
     if (!affectedElement.isValid()) {
       return;
     }

java/structuralsearch-java/src/com/intellij/structuralsearch/JavaStructuralSearchProfile.java

@@ -56,7 +56,7 @@ import java.util.stream.Collectors;
 public class JavaStructuralSearchProfile extends StructuralSearchProfile {
 
   private static final Key<Map<String, ParameterInfo>> PARAMETER_CONTEXT = new Key<>("PARAMETER_CONTEXT");
-  private static final Key<Integer> PARAMETER_LENGTH = new Key<>(("PARAMETER_LENGTH"));
+  private static final Key<Integer> PARAMETER_LENGTH = new Key<>("PARAMETER_LENGTH");
 
   public static final PatternContext DEFAULT_CONTEXT = new PatternContext("default", "Default");
   public static final PatternContext MEMBER_CONTEXT = new PatternContext("member", "Class Member");
@@ -73,7 +73,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
     ContainerUtil.set(MatchOptions.MODIFIER_ANNOTATION_NAME, MatchOptions.INSTANCE_MODIFIER_NAME, PsiModifier.PACKAGE_LOCAL);
 
   @Override
-  public String getText(PsiElement match, int start, int end) {
+  public @NotNull String getText(@NotNull PsiElement match, int start, int end) {
     if (match instanceof PsiIdentifier) {
       final PsiElement parent = match.getParent();
       if (parent instanceof PsiJavaCodeReferenceElement && !(parent instanceof PsiExpression)) {
@@ -97,7 +97,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
 
   @Override
   @NotNull
-  public String getTypedVarString(final PsiElement element) {
+  public String getTypedVarString(final @NotNull PsiElement element) {
     String text;
 
     if (element instanceof PsiReceiverParameter) {
@@ -131,7 +131,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public String getMeaningfulText(PsiElement element) {
+  public String getMeaningfulText(@NotNull PsiElement element) {
     if (element instanceof PsiReferenceExpression && ((PsiReferenceExpression)element).getQualifierExpression() != null) {
       final PsiElement resolve = ((PsiReferenceExpression)element).resolve();
       if (resolve instanceof PsiClass) return element.getText();
@@ -139,7 +139,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
       final PsiElement referencedElement = ((PsiReferenceExpression)element).getReferenceNameElement();
       final String text = referencedElement != null ? referencedElement.getText() : "";
 
-      if (resolve == null && text.length() > 0 && Character.isUpperCase(text.charAt(0))) {
+      if (resolve == null && !text.isEmpty() && Character.isUpperCase(text.charAt(0))) {
         return element.getText();
       }
       return text;
@@ -149,31 +149,30 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
 
   @Override
   @Nullable
-  public String getAlternativeText(PsiElement node, String previousText) {
+  public String getAlternativeText(@NotNull PsiElement node, @NotNull String previousText) {
     // Short class name is matched with fully qualified name
-    if(node instanceof PsiJavaCodeReferenceElement || node instanceof PsiClass) {
+    if (node instanceof PsiJavaCodeReferenceElement || node instanceof PsiClass) {
       final PsiElement element = (node instanceof PsiJavaCodeReferenceElement)
                                  ? ((PsiJavaCodeReferenceElement)node).resolve()
                                  : node;
 
       if (element instanceof PsiClass) {
         String text = ((PsiClass)element).getQualifiedName();
-        if (text != null && text.equals(previousText)) {
+        if (previousText.equals(text)) {
           text = ((PsiClass)element).getName();
         }
 
-        if (text != null) {
-          return text;
-        }
+        return text;
       }
-    } else if (node instanceof PsiLiteralExpression || node instanceof PsiComment) {
+    }
+    else if (node instanceof PsiLiteralExpression || node instanceof PsiComment) {
       return node.getText();
     }
     return null;
   }
 
   @Override
-  public PsiElement updateCurrentNode(PsiElement targetNode) {
+  public @NotNull PsiElement updateCurrentNode(@NotNull PsiElement targetNode) {
     if (targetNode instanceof PsiCodeBlock && ((PsiCodeBlock)targetNode).getStatementCount() == 1) {
       PsiElement targetNodeParent = targetNode.getParent();
       if (targetNodeParent instanceof PsiBlockStatement) {
@@ -188,7 +187,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public PsiElement extendMatchedByDownUp(PsiElement targetNode) {
+  public @NotNull PsiElement extendMatchedByDownUp(@NotNull PsiElement targetNode) {
     if (targetNode instanceof PsiIdentifier) {
       targetNode = targetNode.getParent();
       final PsiElement parent = targetNode.getParent();
@@ -198,7 +197,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public PsiElement extendMatchOnePsiFile(PsiElement file) {
+  public @NotNull PsiElement extendMatchOnePsiFile(@NotNull PsiElement file) {
     if (file instanceof PsiIdentifier) {
       // Searching in previous results
       file = file.getParent();
@@ -208,7 +207,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
 
   @NotNull
   @Override
-  public PsiElement getPresentableElement(PsiElement element) {
+  public PsiElement getPresentableElement(@NotNull PsiElement element) {
     element = super.getPresentableElement(element);
     if (element instanceof PsiReferenceExpression) {
       final PsiElement parent = element.getParent();
@@ -227,7 +226,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void compile(PsiElement[] elements, @NotNull GlobalCompilingVisitor globalVisitor) {
+  public void compile(PsiElement @NotNull [] elements, @NotNull GlobalCompilingVisitor globalVisitor) {
     new JavaCompilingVisitor(globalVisitor).compile(elements);
   }
 
@@ -264,7 +263,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
 
   @NotNull
   @Override
-  public List<MatchPredicate> getCustomPredicates(MatchVariableConstraint constraint, String name, MatchOptions options) {
+  public List<MatchPredicate> getCustomPredicates(@NotNull MatchVariableConstraint constraint, @NotNull String name, @NotNull MatchOptions options) {
     final List<MatchPredicate> result = new SmartList<>();
 
     if (!StringUtil.isEmptyOrSpaces(constraint.getNameOfExprType())) {
@@ -375,7 +374,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
     return result;
   }
 
-  private static boolean shouldTryExpressionPattern(List<PsiElement> elements) {
+  private static boolean shouldTryExpressionPattern(@NotNull List<? extends PsiElement> elements) {
     if (elements.size() >= 1 && elements.size() <= 3) {
       final PsiElement firstElement = elements.get(0);
       if (firstElement instanceof PsiDeclarationStatement) {
@@ -391,7 +390,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
     return false;
   }
 
-  private static boolean shouldTryClassPattern(List<PsiElement> elements) {
+  private static boolean shouldTryClassPattern(@NotNull List<? extends PsiElement> elements) {
     if (elements.isEmpty()) {
       return false;
     }
@@ -447,7 +446,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
 
   @NotNull
   @Override
-  public PsiCodeFragment createCodeFragment(Project project, String text, String contextId) {
+  public PsiCodeFragment createCodeFragment(@NotNull Project project, @NotNull String text, String contextId) {
     final PsiCodeFragmentImpl fragment =
       MEMBER_CONTEXT.getId().equals(contextId)
       ? (PsiCodeFragmentImpl)JavaCodeFragmentFactory.getInstance(project).createMemberCodeFragment(text, null, true)
@@ -457,7 +456,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public String getCodeFragmentText(PsiFile fragment) {
+  public @NotNull String getCodeFragmentText(@NotNull PsiFile fragment) {
     final List<String> imports = StringUtil.split(((JavaCodeFragment)fragment).importsToString(), ",");
     final Map<String, String> importMap =
       imports.stream().collect(Collectors.toMap(s -> s.substring(s.lastIndexOf('.') + 1), Function.identity()));
@@ -493,7 +492,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public boolean shouldShowProblem(PsiErrorElement error) {
+  public boolean shouldShowProblem(@NotNull PsiErrorElement error) {
     final String description = error.getErrorDescription();
     final PsiElement parent = error.getParent();
 
@@ -539,7 +538,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void checkSearchPattern(CompiledPattern pattern) {
+  public void checkSearchPattern(@NotNull CompiledPattern pattern) {
     final ValidatingVisitor visitor = new ValidatingVisitor();
     final NodeIterator nodes = pattern.getNodes();
     while (nodes.hasNext()) {
@@ -550,7 +549,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void checkReplacementPattern(Project project, ReplaceOptions options) {
+  public void checkReplacementPattern(@NotNull Project project, @NotNull ReplaceOptions options) {
     final MatchOptions matchOptions = options.getMatchOptions();
     final LanguageFileType fileType = matchOptions.getFileType();
     final Language dialect = matchOptions.getDialect();
@@ -629,12 +628,12 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public Configuration[] getPredefinedTemplates() {
+  public Configuration @NotNull [] getPredefinedTemplates() {
     return JavaPredefinedConfigurations.createPredefinedTemplates();
   }
 
   @Override
-  public void provideAdditionalReplaceOptions(@NotNull PsiElement node, ReplaceOptions options, ReplacementBuilder builder) {
+  public void provideAdditionalReplaceOptions(@NotNull PsiElement node, @NotNull ReplaceOptions options, @NotNull ReplacementBuilder builder) {
     node.accept(new JavaRecursiveElementWalkingVisitor() {
       @Override
       public void visitReferenceExpression(PsiReferenceExpression expression) {
@@ -656,7 +655,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
         setParameterContext(parameter, parameter.getNameIdentifier(), parameter.getTypeElement());
       }
 
-      private void setParameterContext(PsiElement element, PsiElement nameIdentifier, @Nullable PsiElement scopeElement) {
+      private void setParameterContext(@NotNull PsiElement element, PsiElement nameIdentifier, @Nullable PsiElement scopeElement) {
         final ParameterInfo nameInfo = builder.findParameterization(nameIdentifier);
         if (nameInfo == null) return;
         nameInfo.setArgumentContext(false);
@@ -689,7 +688,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void handleSubstitution(ParameterInfo info, MatchResult match, StringBuilder result, ReplacementInfo replacementInfo) {
+  public void handleSubstitution(@NotNull ParameterInfo info, @NotNull MatchResult match, @NotNull StringBuilder result, @NotNull ReplacementInfo replacementInfo) {
     if (info.getName().equals(match.getName())) {
       final String replacementString;
       boolean forceAddingNewLine = false;
@@ -784,7 +783,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void handleNoSubstitution(ParameterInfo info, StringBuilder result) {
+  public void handleNoSubstitution(@NotNull ParameterInfo info, @NotNull StringBuilder result) {
     final PsiElement element = info.getElement();
     final PsiElement prevSibling = PsiTreeUtil.skipWhitespacesBackward(element);
     if (prevSibling instanceof PsiJavaToken && isRemovableToken(prevSibling)) {
@@ -861,11 +860,11 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public boolean isDocCommentOwner(PsiElement match) {
+  public boolean isDocCommentOwner(@NotNull PsiElement match) {
     return match instanceof PsiMember;
   }
 
-  private static String handleParameter(ParameterInfo info, ReplacementInfo replacementInfo, int offset, String template) {
+  private static String handleParameter(@NotNull ParameterInfo info, ReplacementInfo replacementInfo, int offset, String template) {
     final MatchResult matchResult = replacementInfo.getNamedMatchResult(info.getName());
     assert matchResult != null;
 
@@ -923,7 +922,7 @@ public class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public boolean isApplicableConstraint(String constraintName, @Nullable PsiElement variableNode, boolean completePattern, boolean target) {
+  public boolean isApplicableConstraint(@NotNull String constraintName, @Nullable PsiElement variableNode, boolean completePattern, boolean target) {
     switch (constraintName) {
       case UIUtil.TEXT: return !completePattern;
       case UIUtil.TEXT_HIERARCHY:

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/JavaMatchUtil.java

@@ -7,6 +7,7 @@ import com.intellij.psi.PsiComment;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.javadoc.PsiDocComment;
 import com.intellij.psi.tree.IElementType;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Bas Leijdekkers
@@ -15,7 +16,8 @@ public final class JavaMatchUtil {
 
   private JavaMatchUtil() {}
 
-  public static String getCommentText(PsiComment comment) {
+  @NotNull
+  public static String getCommentText(@NotNull PsiComment comment) {
     if (comment instanceof PsiDocComment) {
       final PsiDocComment docComment = (PsiDocComment)comment;
       final StringBuilder result = new StringBuilder();

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/JavaMatchingVisitor.java

@@ -661,7 +661,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
   }
 
   /** Removes parentheses from the element if it is a parenthesized expression. */
-  private static PsiElement unwrap(PsiElement element, MatchContext context) {
+  private static PsiElement unwrap(PsiElement element, @NotNull MatchContext context) {
     return context.getOptions().isLooseMatching() && element instanceof PsiExpression
            ? PsiUtil.skipParenthesizedExprDown((PsiExpression)element)
            : element;
@@ -690,7 +690,8 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return 0;
   }
 
-  private static PsiTypeElement getInnermostComponentTypeElement(PsiTypeElement typeElement) {
+  @NotNull
+  private static PsiTypeElement getInnermostComponentTypeElement(@NotNull PsiTypeElement typeElement) {
     PsiElement child = typeElement.getFirstChild();
     while (child instanceof PsiTypeElement) {
       typeElement = (PsiTypeElement)child;
@@ -699,6 +700,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return typeElement;
   }
 
+  @Contract("!null->!null; null->null")
   private static PsiElement getInnermostComponent(PsiElement element) {
     if (!(element instanceof PsiTypeElement)) {
       return element;
@@ -721,7 +723,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return (referenceElement != null) ? referenceElement : getInnermostComponentTypeElement(typeElement);
   }
 
-  private static PsiTypeElement[] getTypeParameters(PsiJavaCodeReferenceElement referenceElement, Boolean replaceDiamondWithExplicitTypes) {
+  private static PsiTypeElement[] getTypeParameters(@NotNull PsiJavaCodeReferenceElement referenceElement, Boolean replaceDiamondWithExplicitTypes) {
     final PsiReferenceParameterList referenceElementParameterList = referenceElement.getParameterList();
     if (referenceElementParameterList == null) {
       return null;
@@ -758,7 +760,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return newParameterList == null ? null : newParameterList.getTypeParameterElements();
   }
 
-  private Boolean shouldReplaceDiamondWithExplicitTypes(PsiElement element) {
+  private Boolean shouldReplaceDiamondWithExplicitTypes(@NotNull PsiElement element) {
     if (!(element instanceof PsiJavaCodeReferenceElement)) {
       return Boolean.TRUE;
     }
@@ -782,7 +784,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return Boolean.valueOf(!(typeElement.getType() instanceof PsiDiamondType));
   }
 
-  private boolean matchType(PsiElement patternType, PsiElement matchedType) {
+  private boolean matchType(@NotNull PsiElement patternType, PsiElement matchedType) {
     PsiElement patternElement = getInnermostComponent(patternType);
     PsiElement matchedElement = patternElement instanceof PsiTypeElement && ((PsiTypeElement)patternElement).isInferredType()
                                 ? matchedType
@@ -816,7 +818,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
           if (wildcardType2.isExtends()) {
             return myMatchingVisitor.match(patternElement.getLastChild(), matchedElement.getLastChild());
           }
-          else if (!wildcardType2.isBounded()) {
+          else {
             return myMatchingVisitor.matchOptionally(patternElement.getLastChild(), null);
           }
         }
@@ -862,13 +864,10 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
         regExpPredicate = handler.findRegExpPredicate();
 
         if (regExpPredicate != null) {
-          regExpPredicate.setNodeTextGenerator(new RegExpPredicate.NodeTextGenerator() {
-            @Override
-            public String getText(PsiElement element) {
-              final StringBuilder builder = new StringBuilder(StructuralSearchUtil.getMeaningfulText(element));
-              for (int i = 0; i < matchedArrayDimensions; ++i) builder.append("[]");
-              return builder.toString();
-            }
+          regExpPredicate.setNodeTextGenerator(element -> {
+            final StringBuilder builder = new StringBuilder(StructuralSearchUtil.getMeaningfulText(element));
+            for (int i = 0; i < matchedArrayDimensions; ++i) builder.append("[]");
+            return builder.toString();
           });
         }
         fullTypeResult = true;
@@ -921,21 +920,24 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
   }
 
   @Contract(pure = true)
+  @NotNull
   private static String getText(@NotNull PsiElement element) {
     String result;
     if (element instanceof PsiClass) {
       result = ((PsiClass)element).getQualifiedName();
       if (result == null) result = element.getText();
-    } else if (element instanceof PsiJavaCodeReferenceElement) {
+    }
+    else if (element instanceof PsiJavaCodeReferenceElement) {
       result = ((PsiJavaCodeReferenceElement)element).getCanonicalText();
-    } else {
+    }
+    else {
       result = element.getText();
     }
     final int index = result.indexOf('<');
     return index == -1 ? result : result.substring(0, index);
   }
 
-  private boolean matchWithinHierarchy(PsiElement patternElement, PsiElement matchElement, SubstitutionHandler handler) {
+  private boolean matchWithinHierarchy(@NotNull PsiElement patternElement, PsiElement matchElement, SubstitutionHandler handler) {
     patternElement = StructuralSearchUtil.getParentIfIdentifier(patternElement);
     boolean includeInterfaces = true;
     boolean includeClasses = true;
@@ -1028,7 +1030,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     }
   }
 
-  private void matchArrayOrArguments(PsiNewExpression patternExpression, PsiNewExpression matchExpression) {
+  private void matchArrayOrArguments(@NotNull PsiNewExpression patternExpression, @NotNull PsiNewExpression matchExpression) {
     final PsiType type1 = patternExpression.getType();
     final PsiType type2 = matchExpression.getType();
     if (!myMatchingVisitor.setResult(type1 != null && type2 != null && type1.getArrayDimensions() == type2.getArrayDimensions())) return;
@@ -1056,14 +1058,14 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     }
   }
 
-  private static boolean areZeroLiterals(PsiExpression[] expressions) {
+  private static boolean areZeroLiterals(PsiExpression @NotNull [] expressions) {
     for (PsiExpression expression : expressions) {
       if (!(expression instanceof PsiLiteralExpression) || !expression.getText().equals("0")) return false;
     }
     return true;
   }
 
-  private static boolean matchImplicitQualifier(PsiExpression qualifier, PsiElement reference, MatchContext context) {
+  private static boolean matchImplicitQualifier(@NotNull PsiExpression qualifier, @NotNull PsiElement reference, @NotNull MatchContext context) {
     final PsiElement target = reference instanceof PsiMethodCallExpression
                               ? ((PsiMethodCallExpression)reference).resolveMethod()
                               : ((PsiReference)reference).resolve();
@@ -1114,7 +1116,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     }
   }
 
-  private boolean matchTypeParameters(PsiCallExpression call1, PsiCallExpression call2) {
+  private boolean matchTypeParameters(@NotNull PsiCallExpression call1, @NotNull PsiCallExpression call2) {
     final PsiReferenceParameterList patternParameterList = call1.getTypeArgumentList();
     final PsiTypeElement[] patternTypeElements = patternParameterList.getTypeParameterElements();
     if (patternTypeElements.length == 0) {
@@ -1227,7 +1229,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     myMatchingVisitor.setResult(matchSwitchBlock(expression));
   }
 
-  private boolean matchSwitchBlock(PsiSwitchBlock switchBlock) {
+  private boolean matchSwitchBlock(@NotNull PsiSwitchBlock switchBlock) {
     final PsiSwitchBlock other = (PsiSwitchBlock)myMatchingVisitor.getElement();
 
     if (!myMatchingVisitor.match(switchBlock.getExpression(), other.getExpression())) {
@@ -1257,7 +1259,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     myMatchingVisitor.setResult(matchLabelStatement(statement, (PsiSwitchLabelStatementBase)myMatchingVisitor.getElement()));
   }
 
-  private boolean matchLabelStatement(PsiSwitchLabelStatementBase statement1, PsiSwitchLabelStatementBase statement2) {
+  private boolean matchLabelStatement(@NotNull PsiSwitchLabelStatementBase statement1, @NotNull PsiSwitchLabelStatementBase statement2) {
     final PsiExpressionList values1 = statement1.getCaseValues();
     final PsiExpressionList values2 = statement2.getCaseValues();
     if (statement1.isDefaultCase() && !statement2.isDefaultCase()) {
@@ -1274,7 +1276,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return body.length == 0 || myMatchingVisitor.matchSequentially(body, getBody(statement2));
   }
 
-  private static PsiElement[] getBody(PsiSwitchLabelStatementBase switchLabelStatement) {
+  private static PsiElement @NotNull [] getBody(@NotNull PsiSwitchLabelStatementBase switchLabelStatement) {
     final List<PsiElement> result = new SmartList<>();
     if (switchLabelStatement instanceof PsiSwitchLabeledRuleStatement) {
       final PsiStatement body = ((PsiSwitchLabeledRuleStatement)switchLabelStatement).getBody();
@@ -1689,7 +1691,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     }
   }
 
-  private boolean matchAnnotations(PsiElement pattern, PsiElement matched) {
+  private boolean matchAnnotations(@NotNull PsiElement pattern, PsiElement matched) {
     // can't use PsiAnnotationOwner api because it is not implemented completely yet (see e.g. ClsTypeParameterImpl)
     final PsiAnnotation[] annotations = PsiTreeUtil.getChildrenOfType(pattern, PsiAnnotation.class);
     if (annotations == null) {
@@ -1822,7 +1824,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
   }
 
   @Nullable
-  private <T extends PsiExpression> T getExpression(Class<T> aClass, PsiExpression patternExpression) {
+  private <T extends PsiExpression> T getExpression(@NotNull Class<T> aClass, @NotNull PsiExpression patternExpression) {
     PsiElement other = myMatchingVisitor.getElement();
     if (!myMatchingVisitor.setResult(other instanceof PsiExpression)) {
       return null;
@@ -1833,7 +1835,7 @@ public class JavaMatchingVisitor extends JavaElementVisitor {
     return myMatchingVisitor.setResult(aClass.isInstance(other)) ? aClass.cast(other) : null;
   }
 
-  private <T extends PsiElement> T getElement(Class<T> aClass) {
+  private <T extends PsiElement> T getElement(@NotNull Class<T> aClass) {
     final PsiElement other = myMatchingVisitor.getElement();
     return myMatchingVisitor.setResult(aClass.isInstance(other)) ? aClass.cast(other) : null;
   }

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/compiler/JavaCompilingVisitor.java

@@ -38,17 +38,18 @@ import static com.intellij.structuralsearch.impl.matcher.compiler.GlobalCompilin
  * @author Eugene.Kudelevsky
  */
 public class JavaCompilingVisitor extends JavaRecursiveElementWalkingVisitor {
-  final GlobalCompilingVisitor myCompilingVisitor;
+  @NotNull
+  private final GlobalCompilingVisitor myCompilingVisitor;
 
   @NonNls private static final Pattern COMMENT_PATTERN = Pattern.compile("__\\$_\\w+");
-  static final Set<String> excludedKeywords = ContainerUtil.newHashSet(PsiKeyword.CLASS, PsiKeyword.INTERFACE, PsiKeyword.ENUM,
-                                                                       PsiKeyword.THROWS, PsiKeyword.EXTENDS, PsiKeyword.IMPLEMENTS);
+  private static final Set<String> excludedKeywords = ContainerUtil.newHashSet(PsiKeyword.CLASS, PsiKeyword.INTERFACE, PsiKeyword.ENUM,
+                                                                               PsiKeyword.THROWS, PsiKeyword.EXTENDS, PsiKeyword.IMPLEMENTS);
 
-  public JavaCompilingVisitor(GlobalCompilingVisitor compilingVisitor) {
+  public JavaCompilingVisitor(@NotNull GlobalCompilingVisitor compilingVisitor) {
     myCompilingVisitor = compilingVisitor;
   }
 
-  public void compile(PsiElement[] topLevelElements) {
+  public void compile(PsiElement @NotNull [] topLevelElements) {
     final JavaWordOptimizer optimizer = new JavaWordOptimizer();
     final CompiledPattern pattern = myCompilingVisitor.getContext().getPattern();
     for (PsiElement element : topLevelElements) {
@@ -146,8 +147,8 @@ public class JavaCompilingVisitor extends JavaRecursiveElementWalkingVisitor {
     }
 
     @Override
-    public List<String> getDescendantsOf(String className, boolean includeSelf, Project project) {
-      final SmartList<String> result = new SmartList<>();
+    public @NotNull List<String> getDescendantsOf(@NotNull String className, boolean includeSelf, @NotNull Project project) {
+      List<String> result = new SmartList<>();
 
       // use project and libraries scope, because super class may be outside the scope of the search
       final GlobalSearchScope projectAndLibraries = ProjectScope.getAllScope(project);
@@ -199,7 +200,7 @@ public class JavaCompilingVisitor extends JavaRecursiveElementWalkingVisitor {
       comment.putUserData(CompiledPattern.HANDLER_KEY, handler);
       final RegExpPredicate predicate = handler.findRegExpPredicate();
       if (GlobalCompilingVisitor.isSuitablePredicate(predicate, handler)) {
-        myCompilingVisitor.processTokenizedName(predicate.getRegExp(), true, COMMENT);
+        myCompilingVisitor.processTokenizedName(predicate.getRegExp(), COMMENT);
       }
     }
     else if (!commentText.isEmpty()) {
@@ -210,7 +211,7 @@ public class JavaCompilingVisitor extends JavaRecursiveElementWalkingVisitor {
         if (handler != null) comment.putUserData(CompiledPattern.HANDLER_KEY, handler);
       }
       else {
-        myCompilingVisitor.processTokenizedName(commentText, false, COMMENT);
+        myCompilingVisitor.processTokenizedName(commentText, COMMENT);
       }
     }
   }
@@ -391,9 +392,8 @@ public class JavaCompilingVisitor extends JavaRecursiveElementWalkingVisitor {
 
             for (PsiTypeElement param : typeParameterElements) {
               if (param.getInnermostComponentReferenceElement() != null &&
-                  (myCompilingVisitor.getContext().getPattern().isRealTypedVar(
-                    param.getInnermostComponentReferenceElement().getReferenceNameElement()))
-              ) {
+                  myCompilingVisitor.getContext().getPattern().isRealTypedVar(
+                    param.getInnermostComponentReferenceElement().getReferenceNameElement())) {
                 myCompilingVisitor.setFilterSimple(param, TypeParameterFilter.getInstance());
               }
             }
@@ -566,7 +566,7 @@ public class JavaCompilingVisitor extends JavaRecursiveElementWalkingVisitor {
     if (element.getParent() instanceof PsiClass && handler instanceof SubstitutionHandler) {
       final SubstitutionHandler handler2 = (SubstitutionHandler)handler;
 
-      return (handler2.isStrictSubtype() || handler2.isSubtype());
+      return handler2.isStrictSubtype() || handler2.isSubtype();
     }
     return false;
   }

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/handlers/AnnotationHandler.java

@@ -4,6 +4,7 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
 import com.intellij.structuralsearch.impl.matcher.filters.AnnotationFilter;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Bas
@@ -15,7 +16,7 @@ public class AnnotationHandler extends MatchingHandler {
   }
 
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     if (!super.match(patternNode,matchedNode,context)) {
       return false;
     }

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/handlers/DeclarationStatementHandler.java

@@ -8,6 +8,7 @@ import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
 import com.intellij.structuralsearch.impl.matcher.iterators.SsrFilteringNodeIterator;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -19,7 +20,7 @@ public class DeclarationStatementHandler extends MatchingHandler {
   private MatchingHandler myCommentHandler;
 
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     if (patternNode instanceof PsiComment) {
       return myCommentHandler.match(patternNode, matchedNode, context);
     }

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/handlers/DocDataHandler.java

@@ -7,6 +7,7 @@ import com.intellij.psi.javadoc.PsiDocTagValue;
 import com.intellij.psi.javadoc.PsiDocToken;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
 import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -22,7 +23,7 @@ public class DocDataHandler extends MatchingHandler {
   );
 
   @Override
-  public boolean match(PsiElement node, PsiElement match, MatchContext context) {
+  public boolean match(PsiElement node, PsiElement match, @NotNull MatchContext context) {
     String text1 = node.getText();
 
     text1 = getTextFromNode(node, text1);

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/handlers/ExpressionHandler.java

@@ -4,6 +4,7 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiExpressionStatement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Handler for expression search. The pattern for an expression includes an unnecessary {@code PsiExpressionStatement},
@@ -11,7 +12,7 @@ import com.intellij.structuralsearch.impl.matcher.MatchContext;
  */
 public class ExpressionHandler extends MatchingHandler {
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     if (!super.match(patternNode,matchedNode, context)) {
       return false;
     }

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/handlers/StatementHandler.java

@@ -3,6 +3,7 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 
 import com.intellij.psi.*;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Handler for statement search
@@ -10,7 +11,7 @@ import com.intellij.structuralsearch.impl.matcher.MatchContext;
 public class StatementHandler extends MatchingHandler {
 
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     if (!(matchedNode instanceof PsiStatement) && !(matchedNode instanceof PsiComment)) {
       // typed statement matches statements (including block statements) and comments
       return false;

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/iterators/HierarchyNodeIterator.java

@@ -6,6 +6,7 @@ import com.intellij.psi.*;
 import com.intellij.psi.impl.PsiClassImplUtil;
 import com.intellij.structuralsearch.impl.matcher.MatchUtils;
 import com.intellij.util.SmartList;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.HashSet;
 import java.util.List;
@@ -16,14 +17,14 @@ import java.util.Set;
  */
 public class HierarchyNodeIterator extends NodeIterator {
   private int index;
-  private final List<PsiElement> remaining;
+  private final List<PsiElement> remaining = new SmartList<>();
   private boolean objectTaken;
   private boolean firstElementTaken;
   private final boolean acceptClasses;
   private final boolean acceptInterfaces;
   private final boolean acceptFirstElement;
 
-  private void build(PsiElement current, Set<PsiElement> visited) {
+  private void build(PsiElement current, @NotNull Set<PsiElement> visited) {
     if (current == null) return;
 
     final String text = current instanceof PsiClass ? ((PsiClass)current).getName() : current.getText();
@@ -66,7 +67,7 @@ public class HierarchyNodeIterator extends NodeIterator {
     }
   }
 
-  private void processClasses(PsiReferenceList referenceList, Set<PsiElement> visited) {
+  private void processClasses(PsiReferenceList referenceList, @NotNull Set<PsiElement> visited) {
     if (referenceList == null) {
       return;
     }
@@ -79,8 +80,7 @@ public class HierarchyNodeIterator extends NodeIterator {
     this(reference, acceptClasses, acceptInterfaces, true);
   }
 
-  public HierarchyNodeIterator(PsiElement reference, boolean acceptClasses, boolean acceptInterfaces, boolean acceptFirstElement) {
-    remaining = new SmartList<>();
+  private HierarchyNodeIterator(PsiElement reference, boolean acceptClasses, boolean acceptInterfaces, boolean acceptFirstElement) {
     this.acceptClasses = acceptClasses;
     this.acceptInterfaces = acceptInterfaces;
     this.acceptFirstElement = acceptFirstElement;

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/predicates/ExprTypePredicate.java

@@ -6,6 +6,8 @@ import com.intellij.psi.*;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
 import com.intellij.util.SmartList;
 import gnu.trove.THashSet;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.Collections;
 import java.util.List;
@@ -24,7 +26,7 @@ public class ExprTypePredicate extends MatchPredicate {
   private final boolean myCaseSensitive;
   private final List<String> myTypes;
 
-  public ExprTypePredicate(String type, String baseName, boolean withinHierarchy, boolean caseSensitiveMatch, boolean target, boolean regex) {
+  public ExprTypePredicate(@NotNull String type, String baseName, boolean withinHierarchy, boolean caseSensitiveMatch, boolean target, boolean regex) {
     myDelegate = regex ? new RegExpPredicate(type, caseSensitiveMatch, baseName, false, target) : null;
     myWithinHierarchy = withinHierarchy;
     needsTypeParameters = type.indexOf('<') >= 0;
@@ -35,7 +37,7 @@ public class ExprTypePredicate extends MatchPredicate {
   }
 
   @Override
-  public boolean match(PsiElement match, int start, int end, MatchContext context) {
+  public boolean match(@NotNull PsiElement match, int start, int end, @NotNull MatchContext context) {
     if (match instanceof PsiIdentifier) {
       // since we pickup tokens
       match = match.getParent();
@@ -51,7 +53,7 @@ public class ExprTypePredicate extends MatchPredicate {
     return type != null && doMatchWithTheType(type, context, match, null);
   }
 
-  protected PsiType evalType(PsiExpression match, MatchContext context) {
+  protected PsiType evalType(@NotNull PsiExpression match, @NotNull MatchContext context) {
     if (match instanceof PsiFunctionalExpression) {
       final PsiFunctionalExpression functionalExpression = (PsiFunctionalExpression)match;
       return functionalExpression.getFunctionalInterfaceType();
@@ -65,7 +67,7 @@ public class ExprTypePredicate extends MatchPredicate {
     return match.getType();
   }
 
-  private boolean doMatchWithTheType(final PsiType type, MatchContext context, PsiElement matchedNode, Set<? super PsiType> visited) {
+  private boolean doMatchWithTheType(@NotNull PsiType type, @NotNull MatchContext context, @NotNull PsiElement matchedNode, @Nullable Set<? super PsiType> visited) {
     final List<String> permutations = getTextPermutations(type);
     for (String permutation : permutations) {
       if (myDelegate == null ? doMatch(permutation) : myDelegate.doMatch(permutation, context, matchedNode)) {

java/structuralsearch-java/src/com/intellij/structuralsearch/impl/matcher/predicates/FormalArgTypePredicate.java

@@ -5,10 +5,11 @@ import com.intellij.psi.PsiExpression;
 import com.intellij.psi.PsiType;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
 import com.siyeh.ig.psiutils.ExpectedTypeUtils;
+import org.jetbrains.annotations.NotNull;
 
 public class FormalArgTypePredicate extends ExprTypePredicate {
 
-  public FormalArgTypePredicate(String type,
+  public FormalArgTypePredicate(@NotNull String type,
                                 String baseName,
                                 boolean withinHierarchy,
                                 boolean caseSensitiveMatch,
@@ -18,7 +19,7 @@ public class FormalArgTypePredicate extends ExprTypePredicate {
   }
 
   @Override
-  protected PsiType evalType(PsiExpression match, MatchContext context) {
+  protected PsiType evalType(@NotNull PsiExpression match, @NotNull MatchContext context) {
     return ExpectedTypeUtils.findExpectedType(match, true, true);
   }
 }

platform/analysis-impl/src/com/intellij/codeInspection/ex/DynamicGroupTool.java

@@ -1,8 +1,11 @@
 // Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.codeInspection.ex;
 
+import org.jetbrains.annotations.NotNull;
+
 import java.util.List;
 
 public interface DynamicGroupTool {
+  @NotNull
   List<LocalInspectionToolWrapper> getChildren();
 }

platform/lang-impl/src/com/intellij/profile/codeInspection/ui/InspectionProfileActionProvider.java

@@ -15,5 +15,5 @@ public abstract class InspectionProfileActionProvider {
     ExtensionPointName.create("com.intellij.inspectionProfileActionProvider");
 
   @NotNull
-  public abstract List<AnAction> getActions(SingleInspectionProfilePanel panel);
+  public abstract List<AnAction> getActions(@NotNull SingleInspectionProfilePanel panel);
 }

platform/structuralsearch/source/com/intellij/structuralsearch/DefaultMatchResultSink.java

@@ -17,23 +17,24 @@ package com.intellij.structuralsearch;
 
 import com.intellij.openapi.progress.ProgressIndicator;
 import com.intellij.psi.PsiFile;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Bas Leijdekkers
  */
 public class DefaultMatchResultSink implements MatchResultSink {
   @Override
-  public void newMatch(MatchResult result) {
+  public void newMatch(@NotNull MatchResult result) {
 
   }
 
   @Override
-  public void processFile(PsiFile element) {
+  public void processFile(@NotNull PsiFile element) {
 
   }
 
   @Override
-  public void setMatchingProcess(MatchingProcess matchingProcess) {
+  public void setMatchingProcess(@NotNull MatchingProcess matchingProcess) {
 
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/DocumentBasedReplaceHandler.java

@@ -9,6 +9,7 @@ import com.intellij.psi.PsiDocumentManager;
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.plugin.replace.ReplaceOptions;
 import com.intellij.structuralsearch.plugin.replace.ReplacementInfo;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -25,7 +26,7 @@ public class DocumentBasedReplaceHandler extends StructuralReplaceHandler {
   }
 
   @Override
-  public void replace(ReplacementInfo info, ReplaceOptions options) {
+  public void replace(@NotNull ReplacementInfo info, @NotNull ReplaceOptions options) {
     final RangeMarker rangeMarker = myRangeMarkers.get(info);
     final Document document = rangeMarker.getDocument();
     document.replaceString(rangeMarker.getStartOffset(), rangeMarker.getEndOffset(), info.getReplacement());
@@ -33,7 +34,7 @@ public class DocumentBasedReplaceHandler extends StructuralReplaceHandler {
   }
 
   @Override
-  public void prepare(ReplacementInfo info) {
+  public void prepare(@NotNull ReplacementInfo info) {
     final PsiElement firstElement = StructuralSearchUtil.getPresentableElement(info.getMatch(0));
     if (firstElement == null) return;
     final Document document = PsiDocumentManager.getInstance(myProject).getDocument(firstElement.getContainingFile());

platform/structuralsearch/source/com/intellij/structuralsearch/MalformedPatternException.java

@@ -2,6 +2,7 @@
 package com.intellij.structuralsearch;
 
 import com.intellij.psi.PsiErrorElement;
+import org.jetbrains.annotations.NotNull;
 
 public class MalformedPatternException extends StructuralSearchException {
 
@@ -11,12 +12,12 @@ public class MalformedPatternException extends StructuralSearchException {
     isErrorElement = false;
   }
 
-  public MalformedPatternException(String msg) {
+  public MalformedPatternException(@NotNull String msg) {
     super(msg);
     isErrorElement = false;
   }
 
-  public MalformedPatternException(PsiErrorElement errorElement) {
+  public MalformedPatternException(@NotNull PsiErrorElement errorElement) {
     super(errorElement.getErrorDescription());
     isErrorElement = true;
   }

platform/structuralsearch/source/com/intellij/structuralsearch/MatchOptions.java

@@ -68,11 +68,12 @@ public class MatchOptions implements JDOMExternalizable {
     myPatternContextId = options.myPatternContextId;
   }
 
+  @NotNull
   public MatchOptions copy() {
     return new MatchOptions(this);
   }
 
-  public void initScope(Project project) {
+  public void initScope(@NotNull Project project) {
     if (scope == null && scopeType != null && scopeDescriptor != null) {
       scope = Scopes.createScope(project, scopeDescriptor, scopeType);
     }
@@ -149,7 +150,7 @@ public class MatchOptions implements JDOMExternalizable {
     return pattern;
   }
 
-  public void fillSearchCriteria(String criteria) {
+  public void fillSearchCriteria(@NotNull String criteria) {
     if (!variableConstraints.isEmpty()) variableConstraints.clear();
     StringToConstraintsTransformer.transformCriteria(criteria, this);
   }
@@ -255,7 +256,7 @@ public class MatchOptions implements JDOMExternalizable {
   }
 
   public int hashCode() {
-    int result = (looseMatching ? 1 : 0);
+    int result = looseMatching ? 1 : 0;
     result = 29 * result + (recursiveSearch ? 1 : 0);
     result = 29 * result + (caseSensitiveMatch ? 1 : 0);
     result = 29 * result + pattern.hashCode();
@@ -267,7 +268,7 @@ public class MatchOptions implements JDOMExternalizable {
     return result;
   }
 
-  public void setFileType(LanguageFileType fileType) {
+  public void setFileType(@NotNull LanguageFileType fileType) {
     myFileType = fileType;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/MatchResult.java

@@ -4,6 +4,7 @@ package com.intellij.structuralsearch;
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.plugin.util.SmartPsiPointer;
 import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
@@ -20,6 +21,7 @@ public abstract class MatchResult {
 
   public abstract String getName();
 
+  @NotNull
   public abstract List<MatchResult> getChildren();
   public abstract boolean hasChildren();
   public abstract int size();
@@ -27,6 +29,7 @@ public abstract class MatchResult {
   public abstract boolean isScopeMatch();
   public abstract boolean isMultipleMatch();
 
+  @NotNull
   public abstract MatchResult getRoot();
   public abstract boolean isTarget();
 }

platform/structuralsearch/source/com/intellij/structuralsearch/MatchResultSink.java

@@ -3,6 +3,7 @@ package com.intellij.structuralsearch;
 
 import com.intellij.openapi.progress.ProgressIndicator;
 import com.intellij.psi.PsiFile;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 /**
@@ -11,21 +12,20 @@ import org.jetbrains.annotations.Nullable;
 public interface MatchResultSink {
   /**
    * Notifies sink about new match
-   * @param result
    */
-  void newMatch(MatchResult result);
+  void newMatch(@NotNull MatchResult result);
 
   /**
    *  Notifies sink about starting the matching for given element
    * @param element the current file
    */
-  void processFile(PsiFile element);
+  void processFile(@NotNull PsiFile element);
 
   /**
    * Sets the reference to the matching process
    * @param matchingProcess the matching process reference
    */
-  void setMatchingProcess(MatchingProcess matchingProcess);
+  void setMatchingProcess(@NotNull MatchingProcess matchingProcess);
 
   /**
    * Notifies sink about end of matching.

platform/structuralsearch/source/com/intellij/structuralsearch/MatchVariableConstraint.java

@@ -91,11 +91,11 @@ public class MatchVariableConstraint extends NamedScriptableDefinition {
 
   public MatchVariableConstraint() {}
 
-  public MatchVariableConstraint(String name) {
+  public MatchVariableConstraint(@NotNull String name) {
     setName(name);
   }
 
-  MatchVariableConstraint(MatchVariableConstraint constraint) {
+  private MatchVariableConstraint(@NotNull MatchVariableConstraint constraint) {
     super(constraint);
     regExp = constraint.regExp;
     invertRegExp = constraint.invertRegExp;
@@ -395,7 +395,7 @@ public class MatchVariableConstraint extends NamedScriptableDefinition {
   public boolean equals(Object o) {
     if (this == o) return true;
     if (!(o instanceof MatchVariableConstraint)) return false;
-    if (!(super.equals(o))) return false;
+    if (!super.equals(o)) return false;
 
     final MatchVariableConstraint other = (MatchVariableConstraint)o;
 
@@ -425,8 +425,9 @@ public class MatchVariableConstraint extends NamedScriptableDefinition {
     if (!contextConstraint.equals(other.contextConstraint)) return false;
     if (additionalConstraints != null) {
        if (!additionalConstraints.equals(other.additionalConstraints)) return false;
-    } else if (other.additionalConstraints != null) {
-      return false;
+    }
+    else {
+      return other.additionalConstraints == null;
     }
     return true;
   }

platform/structuralsearch/source/com/intellij/structuralsearch/Matcher.java

@@ -44,24 +44,25 @@ import static com.intellij.structuralsearch.impl.matcher.iterators.SingleNodeIte
  * This class makes program structure tree matching:
  */
 public class Matcher {
-  static final Logger LOG = Logger.getInstance(Matcher.class);
+  private static final Logger LOG = Logger.getInstance(Matcher.class);
 
   @SuppressWarnings("SSBasedInspection")
   private static final ThreadLocal<Set<String>> ourRecursionGuard = ThreadLocal.withInitial(() -> new HashSet<>());
 
   // project being worked on
-  final Project project;
+  private final Project project;
 
   // context of matching
-  final MatchContext matchContext;
+  @NotNull
+  private final MatchContext matchContext;
   private boolean isTesting;
 
   // visitor to delegate the real work
   private final GlobalMatchingVisitor visitor = new GlobalMatchingVisitor();
   private final TaskScheduler scheduler = new TaskScheduler();
 
-  int totalFilesToScan;
-  int scannedFilesCount;
+  private int totalFilesToScan;
+  private int scannedFilesCount;
 
   public Matcher(@NotNull Project project, @NotNull MatchOptions matchOptions) {
     this(project, matchOptions, PatternCompiler.compilePattern(project, matchOptions, false, true));
@@ -69,15 +70,14 @@ public class Matcher {
 
   public Matcher(@NotNull Project project, @NotNull MatchOptions matchOptions, @NotNull CompiledPattern compiledPattern) {
     this.project = project;
-    matchContext = new MatchContext();
-    matchContext.setMatcher(visitor);
+    matchContext = new MatchContext(visitor);
     visitor.setMatchContext(matchContext);
 
     matchContext.setOptions(matchOptions);
     matchContext.setPattern(compiledPattern);
   }
 
-  public static Matcher buildMatcher(Project project, LanguageFileType fileType, String constraint) {
+  public static Matcher buildMatcher(@NotNull Project project, @NotNull LanguageFileType fileType, @NotNull String constraint) {
     if (StringUtil.isQuotedString(constraint)) {
       // keep old configurations working, also useful for testing
       final MatchOptions myMatchOptions = new MatchOptions();
@@ -110,7 +110,7 @@ public class Matcher {
     PatternCompiler.compilePattern(project, options, true, true);
   }
 
-  public boolean checkIfShouldAttemptToMatch(NodeIterator matchedNodes) {
+  public boolean checkIfShouldAttemptToMatch(@NotNull NodeIterator matchedNodes) {
     final CompiledPattern pattern = matchContext.getPattern();
     final NodeIterator patternNodes = pattern.getNodes();
     try {
@@ -168,7 +168,7 @@ public class Matcher {
       return;
     }
 
-    matchContext.getSink().setMatchingProcess( scheduler );
+    matchContext.getSink().setMatchingProcess(scheduler);
     scheduler.init();
 
     if (isTesting) {
@@ -239,7 +239,7 @@ public class Matcher {
     }
   }
 
-  public MatchContext getMatchContext() {
+  public @NotNull MatchContext getMatchContext() {
     return matchContext;
   }
 
@@ -385,7 +385,7 @@ public class Matcher {
    * Initiates the matching process for given element
    * @param element the current search tree element
    */
-  void match(@NotNull PsiElement element) {
+  private void match(@NotNull PsiElement element) {
     final MatchingStrategy strategy = matchContext.getPattern().getStrategy();
 
     if (strategy.continueMatching(element)) {
@@ -430,12 +430,13 @@ public class Matcher {
         }
         while (element.getClass() != targetNode.getClass()) {
           element = element.getParent();
-          if (element == null)  return Collections.emptyList();
+          if (element == null) return Collections.emptyList();
         }
 
         elementToStartMatching = element;
       }
-    } else {
+    }
+    else {
       final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByPsiElement(element);
       if (profile == null) return Collections.emptyList();
       targetNode = profile.extendMatchedByDownUp(targetNode);

platform/structuralsearch/source/com/intellij/structuralsearch/PatternContext.java

@@ -7,14 +7,14 @@ import org.jetbrains.annotations.NotNull;
  * @author Bas Leijdekkers
  */
 public final class PatternContext implements Comparable<PatternContext> {
-
+  @NotNull
   public final String myID;
+  @NotNull
   private final String myDisplayName;
 
-  public PatternContext(@NotNull String ID, String displayName) {
+  public PatternContext(@NotNull String ID, @NotNull String displayName) {
     myID = ID;
     myDisplayName = displayName;
-
   }
 
   @Override
@@ -41,7 +41,7 @@ public final class PatternContext implements Comparable<PatternContext> {
     return myID;
   }
 
-  public String getDisplayName() {
+  public @NotNull String getDisplayName() {
     return myDisplayName;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/PredefinedConfigurationUtil.java

@@ -6,6 +6,8 @@ import com.intellij.openapi.fileTypes.StdFileTypes;
 import com.intellij.structuralsearch.plugin.ui.Configuration;
 import com.intellij.structuralsearch.plugin.ui.SearchConfiguration;
 import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 public final class PredefinedConfigurationUtil {
 
@@ -15,19 +17,22 @@ public final class PredefinedConfigurationUtil {
    * instead.
    */
   @Deprecated
-  public static Configuration createSearchTemplateInfo(String name, @NonNls String criteria, String category) {
+  @NotNull
+  public static Configuration createSearchTemplateInfo(@NotNull String name, @NonNls @NotNull String criteria, @NotNull String category) {
     return createSearchTemplateInfo(name, criteria, category, StdFileTypes.JAVA);
   }
 
-  public static Configuration createSearchTemplateInfo(String name, @NonNls String criteria, String category, LanguageFileType fileType) {
+  @NotNull
+  public static Configuration createSearchTemplateInfo(@NotNull String name, @NonNls @NotNull String criteria, @NotNull String category, @NotNull LanguageFileType fileType) {
     return createSearchTemplateInfo(name, criteria, category, fileType, null);
   }
 
-  public static Configuration createSearchTemplateInfo(String name,
-                                                       @NonNls String criteria,
-                                                       String category,
-                                                       LanguageFileType fileType,
-                                                       PatternContext context) {
+  @NotNull
+  public static Configuration createSearchTemplateInfo(@NotNull String name,
+                                                       @NonNls @NotNull String criteria,
+                                                       @NotNull String category,
+                                                       @NotNull LanguageFileType fileType,
+                                                       @Nullable PatternContext context) {
     final SearchConfiguration config = new SearchConfiguration(name, category);
     config.setPredefined(true);
 

platform/structuralsearch/source/com/intellij/structuralsearch/ReplacementVariableDefinition.java

@@ -1,17 +1,19 @@
 // Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.structuralsearch;
 
+import org.jetbrains.annotations.NotNull;
+
 /**
  * @author Maxim.Mossienko
  */
 public class ReplacementVariableDefinition extends NamedScriptableDefinition {
   public ReplacementVariableDefinition() {}
 
-  public ReplacementVariableDefinition(String name) {
+  public ReplacementVariableDefinition(@NotNull String name) {
     setName(name);
   }
 
-  public ReplacementVariableDefinition(ReplacementVariableDefinition definition) {
+  public ReplacementVariableDefinition(@NotNull ReplacementVariableDefinition definition) {
     super(definition);
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/StructuralReplaceHandler.java

@@ -3,14 +3,15 @@ package com.intellij.structuralsearch;
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.plugin.replace.ReplaceOptions;
 import com.intellij.structuralsearch.plugin.replace.ReplacementInfo;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Eugene.Kudelevsky
  */
 public abstract class StructuralReplaceHandler {
-  public abstract void replace(final ReplacementInfo info, ReplaceOptions options);
+  public abstract void replace(@NotNull ReplacementInfo info, @NotNull ReplaceOptions options);
 
-  public void prepare(ReplacementInfo info) {}
+  public void prepare(@NotNull ReplacementInfo info) {}
 
-  public void postProcess(PsiElement affectedElement, ReplaceOptions options) {}
+  public void postProcess(@NotNull PsiElement affectedElement, @NotNull ReplaceOptions options) {}
 }

platform/structuralsearch/source/com/intellij/structuralsearch/StructuralSearchException.java

@@ -1,17 +1,19 @@
 // Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.structuralsearch;
 
+import org.jetbrains.annotations.NotNull;
+
 /**
  * @author Bas Leijdekkers
  */
 public class StructuralSearchException extends RuntimeException {
   public StructuralSearchException() {}
 
-  public StructuralSearchException(String message) {
+  public StructuralSearchException(@NotNull String message) {
     super(message);
   }
 
-  public StructuralSearchException(Throwable cause) {
+  public StructuralSearchException(@NotNull Throwable cause) {
     super(cause);
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/StructuralSearchProfile.java

@@ -46,10 +46,8 @@ public abstract class StructuralSearchProfile {
    * Creates the pattern PSI tree which is stored inside CompiledPattern.
    * Uses compiling visitor to visit the query PsiElements, sets the correct Filters and Handlers.
    * @see #createCompiledPattern()
-   * @param elements
-   * @param globalVisitor
    */
-  public abstract void compile(PsiElement[] elements, @NotNull GlobalCompilingVisitor globalVisitor);
+  public abstract void compile(PsiElement @NotNull [] elements, @NotNull GlobalCompilingVisitor globalVisitor);
 
   /**
    * The MatchingVisitor knows how to match language specific constructs, when those constructs have already been found.
@@ -70,25 +68,22 @@ public abstract class StructuralSearchProfile {
 
   /**
    * Filter to filter out uninteresting elements that should not be matched. Usually white space and error elements.
-   * @return
    */
   @NotNull
   public abstract NodeFilter getLexicalNodesFilter();
 
   /**
    * Creates language specific compiled pattern.
-   * @return
    */
   @NotNull
   public abstract CompiledPattern createCompiledPattern();
 
   @NotNull
-  public List<MatchPredicate> getCustomPredicates(MatchVariableConstraint constraint, String name, MatchOptions options) {
+  public List<MatchPredicate> getCustomPredicates(@NotNull MatchVariableConstraint constraint, @NotNull String name, @NotNull MatchOptions options) {
     return Collections.emptyList();
   }
 
   /**
-   * @param language
    * @return true, if this structural search profile can match code of the specified language. False otherwise.
    */
   public abstract boolean isMyLanguage(@NotNull Language language);
@@ -96,32 +91,25 @@ public abstract class StructuralSearchProfile {
   /**
    * Converts query text into PSI tree.
    * @param text  the text of the search query.
-   * @param context
-   * @param fileType
-   * @param language
-   * @param contextId
-   * @param project
-   * @param physical
-   * @return
    */
   @NotNull
-  public PsiElement[] createPatternTree(@NotNull String text,
-                                        @NotNull PatternTreeContext context,
-                                        @NotNull LanguageFileType fileType,
-                                        @NotNull Language language,
-                                        @Nullable String contextId,
-                                        @NotNull Project project,
-                                        boolean physical) {
+  public PsiElement @NotNull [] createPatternTree(@NotNull String text,
+                                                  @NotNull PatternTreeContext context,
+                                                  @NotNull LanguageFileType fileType,
+                                                  @NotNull Language language,
+                                                  @Nullable String contextId,
+                                                  @NotNull Project project,
+                                                  boolean physical) {
     return doCreatePatternTree(text, context, fileType, language, project, physical, getContext(text, language, contextId));
   }
 
   @NotNull
-  public PsiElement[] createPatternTree(@NotNull String text,
-                                        @NotNull PatternContextInfo contextInfo,
-                                        @NotNull LanguageFileType fileType,
-                                        @NotNull Language language,
-                                        @NotNull Project project,
-                                        boolean physical) {
+  public PsiElement @NotNull [] createPatternTree(@NotNull String text,
+                                                  @NotNull PatternContextInfo contextInfo,
+                                                  @NotNull LanguageFileType fileType,
+                                                  @NotNull Language language,
+                                                  @NotNull Project project,
+                                                  boolean physical) {
     String contextConstraint = contextInfo.getContextConstraint();
     if (StringUtil.isEmpty(contextConstraint)) {
       PatternContext patternContext = contextInfo.getPatternContext();
@@ -132,13 +120,13 @@ public abstract class StructuralSearchProfile {
   }
 
   @NotNull
-  private PsiElement[] doCreatePatternTree(@NotNull String text,
-                                           @NotNull PatternTreeContext context,
-                                           @NotNull LanguageFileType fileType,
-                                           @NotNull Language language,
-                                           @NotNull Project project,
-                                           boolean physical,
-                                           String strContext) {
+  private PsiElement @NotNull [] doCreatePatternTree(@NotNull String text,
+                                                     @NotNull PatternTreeContext context,
+                                                     @NotNull LanguageFileType fileType,
+                                                     @NotNull Language language,
+                                                     @NotNull Project project,
+                                                     boolean physical,
+                                                     @NotNull String strContext) {
     String placeholderName = getPlaceholderVarName();
     final String patternInContext = (context == PatternTreeContext.File) ? text : strContext.replace(placeholderName, text);
 
@@ -207,14 +195,15 @@ public abstract class StructuralSearchProfile {
   }
 
   @Nullable
-  public PsiCodeFragment createCodeFragment(Project project, String text, String contextId) {
+  public PsiCodeFragment createCodeFragment(@NotNull Project project, @NotNull String text, @Nullable String contextId) {
     return null;
   }
 
   /**
    * This method is called while holding a read action.
    */
-  public String getCodeFragmentText(PsiFile fragment) {
+  @NotNull
+  public String getCodeFragmentText(@NotNull PsiFile fragment) {
     return fragment.getText();
   }
 
@@ -245,14 +234,14 @@ public abstract class StructuralSearchProfile {
     return false;
   }
 
-  public void checkSearchPattern(CompiledPattern pattern) {}
+  public void checkSearchPattern(@NotNull CompiledPattern pattern) {}
 
-  public void checkReplacementPattern(Project project, ReplaceOptions options) {
+  public void checkReplacementPattern(@NotNull Project project, @NotNull ReplaceOptions options) {
     final String fileType = StringUtil.toLowerCase(options.getMatchOptions().getFileType().getName());
     throw new UnsupportedPatternException(SSRBundle.message("replacement.not.supported.for.filetype", fileType));
   }
 
-  public boolean shouldShowProblem(PsiErrorElement error) {
+  public boolean shouldShowProblem(@NotNull PsiErrorElement error) {
     return false;
   }
 
@@ -261,14 +250,15 @@ public abstract class StructuralSearchProfile {
     return false;
   }
 
-  public String getText(PsiElement match, int start, int end) {
+  @NotNull
+  public String getText(@NotNull PsiElement match, int start, int end) {
     final String matchText = match.getText();
     if (start == 0 && end == -1) return matchText;
     return matchText.substring(start, end == -1 ? matchText.length() : end);
   }
 
   @NotNull
-  public String getTypedVarString(PsiElement element) {
+  public String getTypedVarString(@NotNull PsiElement element) {
     if (element instanceof PsiNamedElement) {
       final String name = ((PsiNamedElement)element).getName();
       if (name != null) {
@@ -278,23 +268,26 @@ public abstract class StructuralSearchProfile {
     return element.getText();
   }
 
-  public String getMeaningfulText(PsiElement element) {
+  public String getMeaningfulText(@NotNull PsiElement element) {
     return getTypedVarString(element);
   }
 
-  public String getAlternativeText(PsiElement element, String previousText) {
+  public String getAlternativeText(@NotNull PsiElement element, @NotNull String previousText) {
     return null;
   }
 
-  public PsiElement updateCurrentNode(PsiElement node) {
+  @NotNull
+  public PsiElement updateCurrentNode(@NotNull PsiElement node) {
     return node;
   }
 
-  public PsiElement extendMatchedByDownUp(PsiElement node) {
+  @NotNull
+  public PsiElement extendMatchedByDownUp(@NotNull PsiElement node) {
     return node;
   }
 
-  public PsiElement extendMatchOnePsiFile(PsiElement file) {
+  @NotNull
+  public PsiElement extendMatchOnePsiFile(@NotNull PsiElement file) {
     return file;
   }
 
@@ -302,13 +295,13 @@ public abstract class StructuralSearchProfile {
     return fileType;
   }
 
-  public Configuration[] getPredefinedTemplates() {
+  public Configuration @NotNull [] getPredefinedTemplates() {
     return Configuration.EMPTY_ARRAY;
   }
 
-  public void provideAdditionalReplaceOptions(@NotNull PsiElement node, ReplaceOptions options, ReplacementBuilder builder) {}
+  public void provideAdditionalReplaceOptions(@NotNull PsiElement node, @NotNull ReplaceOptions options, @NotNull ReplacementBuilder builder) {}
 
-  public void handleSubstitution(ParameterInfo info, MatchResult match, StringBuilder result, ReplacementInfo replacementInfo) {
+  public void handleSubstitution(@NotNull ParameterInfo info, @NotNull MatchResult match, @NotNull StringBuilder result, @NotNull ReplacementInfo replacementInfo) {
     if (info.getName().equals(match.getName())) {
       final String replacementString;
       boolean removeSemicolon = false;
@@ -350,7 +343,7 @@ public abstract class StructuralSearchProfile {
     }
   }
 
-  public void handleNoSubstitution(ParameterInfo info, StringBuilder result) {
+  public void handleNoSubstitution(@NotNull ParameterInfo info, @NotNull StringBuilder result) {
     if (info.isHasCommaBefore()) {
       result.delete(info.getBeforeDelimiterPos(), info.getBeforeDelimiterPos() + 1);
     }
@@ -369,12 +362,12 @@ public abstract class StructuralSearchProfile {
     return Collections.emptySet();
   }
 
-  public boolean isDocCommentOwner(PsiElement match) {
+  public boolean isDocCommentOwner(@NotNull PsiElement match) {
     return false;
   }
 
-  @Contract("!null -> !null")
-  public PsiElement getPresentableElement(PsiElement element) {
+  @NotNull
+  public PsiElement getPresentableElement(@NotNull PsiElement element) {
     return isIdentifier(element) ? element.getParent() : element;
   }
 
@@ -388,7 +381,7 @@ public abstract class StructuralSearchProfile {
    * @param target          true, if the current variableNode is the target of the search
    * @return true, if the requested constraint is applicable and the corresponding UI should be shown when editing the variable; false otherwise
    */
-  public boolean isApplicableConstraint(String constraintName, @Nullable PsiElement variableNode, boolean completePattern, boolean target) {
+  public boolean isApplicableConstraint(@NotNull String constraintName, @Nullable PsiElement variableNode, boolean completePattern, boolean target) {
     switch (constraintName) {
       case UIUtil.MINIMUM_ZERO:
         if (target) return false;
@@ -400,8 +393,8 @@ public abstract class StructuralSearchProfile {
     return false;
   }
 
-  public final boolean isApplicableConstraint(String constraintName,
-                                              List<? extends PsiElement> nodes,
+  public final boolean isApplicableConstraint(@NotNull String constraintName,
+                                              @NotNull List<? extends PsiElement> nodes,
                                               boolean completePattern,
                                               boolean target) {
     if (nodes.isEmpty()) {

platform/structuralsearch/source/com/intellij/structuralsearch/StructuralSearchProfileBase.java

@@ -41,7 +41,7 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
   private static final String DELIMITER_CHARS = ",;.[]{}():";
 
   @Override
-  public void compile(PsiElement[] elements, @NotNull final GlobalCompilingVisitor globalVisitor) {
+  public void compile(PsiElement @NotNull [] elements, @NotNull final GlobalCompilingVisitor globalVisitor) {
     final PsiElement topElement = elements[0].getParent();
     final PsiElement element = elements.length > 1 ? topElement : elements[0];
 
@@ -179,14 +179,14 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
   protected abstract LanguageFileType getFileType();
 
   @Override
-  public void checkReplacementPattern(Project project, ReplaceOptions options) {}
+  public void checkReplacementPattern(@NotNull Project project, @NotNull ReplaceOptions options) {}
 
   @Override
   public StructuralReplaceHandler getReplaceHandler(@NotNull Project project, @NotNull ReplaceOptions replaceOptions) {
     return new DocumentBasedReplaceHandler(project);
   }
 
-  static boolean canBePatternVariable(PsiElement element) {
+  private static boolean canBePatternVariable(@NotNull PsiElement element) {
     // can be leaf element! (ex. var a = 1 <-> var $a$ = 1)
     if (element instanceof LeafElement) {
       return true;
@@ -213,7 +213,7 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
     return false;
   }
 
-  static boolean canBePatternVariableValue(PsiElement element) {
+  private static boolean canBePatternVariableValue(@NotNull PsiElement element) {
     // can be leaf element! (ex. var a = 1 <-> var $a$ = 1)
     return !containsOnlyDelimiters(element.getText());
   }
@@ -251,7 +251,7 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
       }
     }
 
-    private void doVisitElement(PsiElement element) {
+    private void doVisitElement(@NotNull PsiElement element) {
       final CompiledPattern pattern = myGlobalVisitor.getContext().getPattern();
 
       if (myGlobalVisitor.getCodeBlockLevel() == 0) {
@@ -262,12 +262,7 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
       if (canBePatternVariable(element) && pattern.isRealTypedVar(element)) {
         myGlobalVisitor.handle(element);
         final MatchingHandler handler = pattern.getHandler(element);
-        handler.setFilter(new NodeFilter() {
-          @Override
-          public boolean accepts(PsiElement other) {
-            return canBePatternVariableValue(other);
-          }
-        });
+        handler.setFilter(other -> canBePatternVariableValue(other));
 
         super.visitElement(element);
 
@@ -283,7 +278,7 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
 
           // todo: support variables inside comments
           if (StringUtil.isJavaIdentifier(text)) {
-            myGlobalVisitor.processTokenizedName(text, true, GlobalCompilingVisitor.OccurenceKind.CODE);
+            myGlobalVisitor.processTokenizedName(text, GlobalCompilingVisitor.OccurenceKind.CODE);
           }
         }
       }
@@ -456,13 +451,13 @@ public abstract class StructuralSearchProfileBase extends StructuralSearchProfil
   private static class MySubstitutionHandler extends SubstitutionHandler {
     final Set<PsiElement> myExceptedNodes;
 
-    MySubstitutionHandler(String name, boolean target, int minOccurs, int maxOccurs, boolean greedy) {
+    MySubstitutionHandler(@NotNull String name, boolean target, int minOccurs, int maxOccurs, boolean greedy) {
       super(name, target, minOccurs, maxOccurs, greedy);
       myExceptedNodes = new HashSet<>();
     }
 
     @Override
-    public boolean matchSequentially(NodeIterator patternNodes, NodeIterator matchNodes, MatchContext context) {
+    public boolean matchSequentially(@NotNull NodeIterator patternNodes, @NotNull NodeIterator matchNodes, @NotNull MatchContext context) {
       if (doMatchSequentially(patternNodes, matchNodes, context)) {
         return true;
       }

platform/structuralsearch/source/com/intellij/structuralsearch/StructuralSearchUtil.java

@@ -26,12 +26,12 @@ import java.util.stream.Collectors;
 public final class StructuralSearchUtil {
   private static final String REG_EXP_META_CHARS = ".$|()[]{}^?*+\\";
   private static final Pattern ACCENTS = Pattern.compile("\\p{InCombiningDiacriticalMarks}+");
-  private static LanguageFileType ourDefaultFileType = null;
+  private static LanguageFileType ourDefaultFileType;
 
-  private static boolean ourUseUniversalMatchingAlgorithm = false;
+  private static boolean ourUseUniversalMatchingAlgorithm;
   private static final Map<String, StructuralSearchProfile> cache = new HashMap<>();
 
-  private static List<Configuration> ourPredefinedConfigurations = null;
+  private static List<Configuration> ourPredefinedConfigurations;
   static {
     StructuralSearchProfile.EP_NAME.addChangeListener(() -> {
       ourPredefinedConfigurations = null;
@@ -53,7 +53,7 @@ public final class StructuralSearchUtil {
   }
 
   @Nullable
-  public static StructuralSearchProfile getProfileByFileType(LanguageFileType fileType) {
+  public static StructuralSearchProfile getProfileByFileType(@NotNull LanguageFileType fileType) {
     return getProfileByLanguage(fileType.getLanguage());
   }
 
@@ -81,7 +81,7 @@ public final class StructuralSearchUtil {
   }
 
   public static PsiElement getParentIfIdentifier(PsiElement element) {
-    return !isIdentifier(element) ? element : element.getParent();
+    return isIdentifier(element) ? element.getParent() : element;
   }
 
   @Contract("!null -> !null")
@@ -146,7 +146,8 @@ public final class StructuralSearchUtil {
     return REG_EXP_META_CHARS.indexOf(ch) >= 0;
   }
 
-  public static String shieldRegExpMetaChars(String word) {
+  @NotNull
+  public static String shieldRegExpMetaChars(@NotNull String word) {
     return shieldRegExpMetaChars(word, new StringBuilder(word.length())).toString();
   }
 
@@ -193,7 +194,7 @@ public final class StructuralSearchUtil {
     return ourPredefinedConfigurations;
   }
 
-  public static boolean isDocCommentOwner(PsiElement match) {
+  public static boolean isDocCommentOwner(@NotNull PsiElement match) {
     final StructuralSearchProfile profile = getProfileByPsiElement(match);
     return profile != null && profile.isDocCommentOwner(match);
   }
@@ -203,11 +204,12 @@ public final class StructuralSearchUtil {
     return profile != null ? profile.getMeaningfulText(matchedNode) : matchedNode.getText();
   }
 
-  public static String getAlternativeText(PsiElement matchedNode, String previousText) {
+  public static String getAlternativeText(@NotNull PsiElement matchedNode, @NotNull String previousText) {
     final StructuralSearchProfile profile = getProfileByPsiElement(matchedNode);
     return profile != null ? profile.getAlternativeText(matchedNode, previousText) : null;
   }
 
+  @NotNull
   public static String normalizeWhiteSpace(@NotNull String text) {
     text = text.trim();
     final StringBuilder result = new StringBuilder();
@@ -228,10 +230,12 @@ public final class StructuralSearchUtil {
     return result.toString();
   }
 
+  @NotNull
   public static String stripAccents(@NotNull String input) {
     return ACCENTS.matcher(Normalizer.normalize(input, Normalizer.Form.NFD)).replaceAll("");
   }
 
+  @NotNull
   public static String normalize(@NotNull String text) {
     return stripAccents(normalizeWhiteSpace(text));
   }

platform/structuralsearch/source/com/intellij/structuralsearch/XmlStructuralSearchProfile.java

@@ -38,7 +38,7 @@ import static com.intellij.structuralsearch.PredefinedConfigurationUtil.createSe
 public class XmlStructuralSearchProfile extends StructuralSearchProfile {
 
   @Override
-  public void compile(PsiElement[] elements, @NotNull GlobalCompilingVisitor globalVisitor) {
+  public void compile(PsiElement @NotNull [] elements, @NotNull GlobalCompilingVisitor globalVisitor) {
     new XmlCompilingVisitor(globalVisitor).compile(elements);
   }
 
@@ -55,7 +55,7 @@ public class XmlStructuralSearchProfile extends StructuralSearchProfile {
 
   @NotNull
   @Override
-  public String getTypedVarString(PsiElement element) {
+  public String getTypedVarString(@NotNull PsiElement element) {
     return element instanceof XmlText ? element.getText().trim() : super.getTypedVarString(element);
   }
 
@@ -102,7 +102,7 @@ public class XmlStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public PsiElement extendMatchedByDownUp(PsiElement node) {
+  public @NotNull PsiElement extendMatchedByDownUp(@NotNull PsiElement node) {
     if (XmlUtil.isXmlToken(node, XmlTokenType.XML_DATA_CHARACTERS)) {
       final PsiElement parent = node.getParent();
       if (parent.getTextRange().equals(node.getTextRange())) {
@@ -130,7 +130,7 @@ public class XmlStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void checkSearchPattern(CompiledPattern pattern) {
+  public void checkSearchPattern(@NotNull CompiledPattern pattern) {
     final ValidatingVisitor visitor = new ValidatingVisitor();
     final NodeIterator nodes = pattern.getNodes();
     while (nodes.hasNext()) {
@@ -159,7 +159,7 @@ public class XmlStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public void checkReplacementPattern(Project project, ReplaceOptions options) {
+  public void checkReplacementPattern(@NotNull Project project, @NotNull ReplaceOptions options) {
   }
 
   @Override
@@ -178,7 +178,7 @@ public class XmlStructuralSearchProfile extends StructuralSearchProfile {
     }
 
     @Override
-    public void replace(ReplacementInfo info, ReplaceOptions options) {
+    public void replace(@NotNull ReplacementInfo info, @NotNull ReplaceOptions options) {
       final PsiElement elementToReplace = StructuralSearchUtil.getPresentableElement(info.getMatch(0));
       assert elementToReplace != null;
       final String replacementToMake = info.getReplacement();
@@ -240,7 +240,7 @@ public class XmlStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   @Override
-  public Configuration[] getPredefinedTemplates() {
+  public Configuration @NotNull [] getPredefinedTemplates() {
     return XmlPredefinedConfigurations.createPredefinedTemplates();
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/CompiledPattern.java

@@ -42,7 +42,7 @@ public abstract class CompiledPattern {
   public abstract String @NotNull [] getTypedVarPrefixes();
   public abstract boolean isTypedVar(@NotNull String str);
 
-  public void setTargetNode(PsiElement element) {
+  public void setTargetNode(@NotNull PsiElement element) {
     targetNode = element;
   }
 
@@ -113,11 +113,11 @@ public abstract class CompiledPattern {
     return handler;
   }
 
-  public MatchingHandler getHandler(String name) {
+  public MatchingHandler getHandler(@NotNull String name) {
     return handlers.get(name);
   }
 
-  public void setHandler(PsiElement node, MatchingHandler handler) {
+  public void setHandler(@NotNull PsiElement node, @NotNull MatchingHandler handler) {
     last = null;
     handlers.put(node, handler);
   }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/GlobalMatchingVisitor.java

@@ -64,13 +64,14 @@ public class GlobalMatchingVisitor extends AbstractMatchingVisitor {
     return this.myResult = result;
   }
 
+  @NotNull
   public MatchContext getMatchContext() {
     return matchContext;
   }
 
   @Override
   protected boolean doMatchInAnyOrder(@NotNull NodeIterator elements, @NotNull NodeIterator elements2) {
-    return matchContext.getPattern().getHandler(elements.current()).matchInAnyOrder(
+    return MatchingHandler.matchInAnyOrder(
       elements,
       elements2,
       matchContext
@@ -217,7 +218,7 @@ public class GlobalMatchingVisitor extends AbstractMatchingVisitor {
     }
   }
 
-  public void setMatchContext(MatchContext matchContext) {
+  public void setMatchContext(@NotNull MatchContext matchContext) {
     this.matchContext = matchContext;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/MatchContext.java

@@ -17,6 +17,10 @@ import java.util.List;
  * Global context of matching process
  */
 public class MatchContext {
+  public MatchContext(@NotNull GlobalMatchingVisitor visitor) {
+    matcher = visitor;
+  }
+
   private final Stack<MatchedElementsListener> myMatchedElementsListenerStack = new Stack<>(2);
 
   private MatchResultSink sink;
@@ -24,7 +28,8 @@ public class MatchContext {
   private MatchResultImpl result;
   private CompiledPattern pattern;
   private MatchOptions options;
-  private GlobalMatchingVisitor matcher;
+  @NotNull
+  private final GlobalMatchingVisitor matcher;
   private boolean shouldRecursivelyMatch = true;
 
   private final Stack<List<PsiElement>> mySavedMatchedNodes = new Stack<>();
@@ -53,14 +58,10 @@ public class MatchContext {
 
   @FunctionalInterface
   public interface MatchedElementsListener {
-    void matchedElements(@NotNull Collection<PsiElement> matchedElements);
+    void matchedElements(@NotNull Collection<? extends PsiElement> matchedElements);
   }
 
-  public void setMatcher(GlobalMatchingVisitor matcher) {
-    this.matcher = matcher;
-  }
-
-  public GlobalMatchingVisitor getMatcher() {
+  public @NotNull GlobalMatchingVisitor getMatcher() {
     return matcher;
   }
 
@@ -68,7 +69,7 @@ public class MatchContext {
     return options;
   }
 
-  public void setOptions(MatchOptions options) {
+  public void setOptions(@NotNull MatchOptions options) {
     this.options = options;
   }
 
@@ -87,6 +88,7 @@ public class MatchContext {
     }
   }
 
+  @NotNull
   public MatchResultImpl getResult() {
     if (result==null) result = new MatchResultImpl();
     return result;
@@ -116,7 +118,7 @@ public class MatchContext {
     return pattern;
   }
 
-  public void setPattern(CompiledPattern pattern) {
+  public void setPattern(@NotNull CompiledPattern pattern) {
     this.pattern = pattern;
   }
 
@@ -124,7 +126,7 @@ public class MatchContext {
     return sink;
   }
 
-  public void setSink(MatchResultSink sink) {
+  public void setSink(@NotNull MatchResultSink sink) {
     this.sink = sink;
   }
 
@@ -140,7 +142,7 @@ public class MatchContext {
     this.shouldRecursivelyMatch = shouldRecursivelyMatch;
   }
 
-  public void pushMatchedElementsListener(MatchedElementsListener matchedElementsListener) {
+  public void pushMatchedElementsListener(@NotNull MatchedElementsListener matchedElementsListener) {
     myMatchedElementsListenerStack.push(matchedElementsListener);
   }
 
@@ -148,7 +150,7 @@ public class MatchContext {
     myMatchedElementsListenerStack.pop();
   }
 
-  public void notifyMatchedElements(Collection<PsiElement> matchedElements) {
+  public void notifyMatchedElements(@NotNull Collection<? extends PsiElement> matchedElements) {
     if (!myMatchedElementsListenerStack.isEmpty()) {
       myMatchedElementsListenerStack.peek().matchedElements(matchedElements);
     }
@@ -167,7 +169,7 @@ public class MatchContext {
     getSink().newMatch(result);
   }
 
-  private boolean doDispatch(final MatchResult result) {
+  private boolean doDispatch(@NotNull MatchResult result) {
     boolean ret = false;
 
     for (MatchResult r : result.getChildren()) {
@@ -182,7 +184,7 @@ public class MatchContext {
     return ret;
   }
 
-  private static void processNoSubstitutionMatch(List<PsiElement> matchedNodes, MatchResultImpl result) {
+  private static void processNoSubstitutionMatch(@NotNull List<? extends PsiElement> matchedNodes, @NotNull MatchResultImpl result) {
     final boolean complexMatch = matchedNodes.size() > 1;
     final PsiElement match = matchedNodes.get(0);
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/MatchResultImpl.java

@@ -5,6 +5,8 @@ import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.MatchResult;
 import com.intellij.structuralsearch.plugin.util.SmartPsiPointer;
 import com.intellij.util.SmartList;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.Collections;
 import java.util.List;
@@ -20,16 +22,16 @@ public final class MatchResultImpl extends MatchResult {
 
   private boolean myScopeMatch;
   private boolean myMultipleMatch;
-  private MatchResultImpl parent = null;
+  private MatchResultImpl parent;
 
   MatchResultImpl() {
   }
 
-  public MatchResultImpl(String name, String image, SmartPsiPointer ref, boolean target) {
-    this(name,image,ref,0,-1,target);
+  public MatchResultImpl(@NotNull String name, @Nullable String image, @NotNull SmartPsiPointer ref, boolean target) {
+    this(name, image, ref, 0, -1, target);
   }
 
-  public MatchResultImpl(String name, String image, SmartPsiPointer ref, int start, int end, boolean target) {
+  public MatchResultImpl(@NotNull String name, @Nullable String image, @NotNull SmartPsiPointer ref, int start, int end, boolean target) {
     matchRef = ref;
     this.name = name;
     matchImage = image;
@@ -56,7 +58,7 @@ public final class MatchResultImpl extends MatchResult {
     return matchRef.getElement();
   }
 
-  public void setMatchRef(SmartPsiPointer matchStart) {
+  public void setMatchRef(@NotNull SmartPsiPointer matchStart) {
     matchRef = matchStart;
   }
 
@@ -65,12 +67,12 @@ public final class MatchResultImpl extends MatchResult {
     return name;
   }
 
-  public void setName(String name) {
+  public void setName(@NotNull String name) {
     this.name = name;
   }
 
   @Override
-  public List<MatchResult> getChildren() {
+  public @NotNull List<MatchResult> getChildren() {
     return Collections.unmodifiableList(myChildren);
   }
 
@@ -90,21 +92,6 @@ public final class MatchResultImpl extends MatchResult {
     return myMultipleMatch;
   }
 
-  public void clear() {
-    if (matchRef != null) {
-      matchRef.clear();
-      matchRef = null;
-    }
-
-    for (final MatchResult match : myChildren) {
-      ((MatchResultImpl)match).clear();
-    }
-    myChildren.clear();
-
-    name = null;
-    matchImage = null;
-  }
-
   @Override
   public boolean hasChildren() {
     return !myChildren.isEmpty();
@@ -114,6 +101,7 @@ public final class MatchResultImpl extends MatchResult {
     myChildren.clear();
   }
 
+  @NotNull
   public MatchResult removeLastChild() {
     return myChildren.remove(myChildren.size() - 1);
   }
@@ -126,7 +114,7 @@ public final class MatchResultImpl extends MatchResult {
     myMultipleMatch = multipleMatch;
   }
 
-  public MatchResultImpl findChild(String name) {
+  public MatchResultImpl findChild(@NotNull String name) {
     // @todo this could be performance bottleneck, replace with hash lookup!
     for (final MatchResult match : myChildren) {
       final MatchResultImpl res = (MatchResultImpl)match;
@@ -138,7 +126,7 @@ public final class MatchResultImpl extends MatchResult {
     return null;
   }
 
-  public static MatchResultImpl findChildDeep(MatchResult match , String name) {
+  public static MatchResultImpl findChildDeep(@NotNull MatchResult match, @NotNull String name) {
     for (MatchResult child : match.getChildren()) {
       if (name.equals(child.getName())) {
         return (MatchResultImpl)child;
@@ -151,7 +139,7 @@ public final class MatchResultImpl extends MatchResult {
     return null;
   }
 
-  public MatchResult removeChild(String typedVar) {
+  public MatchResult removeChild(@NotNull String typedVar) {
     // @todo this could be performance bottleneck, replace with hash lookup!
     for (int i = 0, size = myChildren.size(); i < size; i++) {
       final MatchResult child = myChildren.get(i);
@@ -164,7 +152,7 @@ public final class MatchResultImpl extends MatchResult {
     return null;
   }
 
-  public void addChild(MatchResult result) {
+  public void addChild(@NotNull MatchResult result) {
     if (result instanceof MatchResultImpl) {
       ((MatchResultImpl)result).parent = this;
     }
@@ -172,7 +160,7 @@ public final class MatchResultImpl extends MatchResult {
   }
 
   @Override
-  public MatchResult getRoot() {
+  public @NotNull MatchResult getRoot() {
     if (parent == null) return this;
     MatchResultImpl root = parent;
     while (root.parent != null) {
@@ -181,7 +169,7 @@ public final class MatchResultImpl extends MatchResult {
     return root;
   }
 
-  public void setMatchImage(String matchImage) {
+  public void setMatchImage(@NotNull String matchImage) {
     this.matchImage = matchImage;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/MatcherImplUtil.java

@@ -8,21 +8,25 @@ import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.PatternContextInfo;
 import com.intellij.structuralsearch.StructuralSearchProfile;
 import com.intellij.structuralsearch.StructuralSearchUtil;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Maxim.Mossienko
  */
 public final class MatcherImplUtil {
 
-  public static PsiElement[] createTreeFromText(String text, PatternTreeContext context, LanguageFileType fileType, Project project) {
-    return createTreeFromText(text, new PatternContextInfo(context), fileType, null, project, false);
+  public static PsiElement @NotNull [] createTreeFromText(@NotNull String text,
+                                                          @NotNull PatternTreeContext context,
+                                                          @NotNull LanguageFileType fileType,
+                                                          @NotNull Project project) {
+    return createTreeFromText(text, new PatternContextInfo(context), fileType, fileType.getLanguage(), project, false);
   }
 
-  public static PsiElement[] createSourceTreeFromText(String text,
-                                                      PatternTreeContext context,
-                                                      LanguageFileType fileType,
-                                                      Project project,
-                                                      boolean physical) {
+  public static PsiElement @NotNull [] createSourceTreeFromText(@NotNull String text,
+                                                                @NotNull PatternTreeContext context,
+                                                                @NotNull LanguageFileType fileType,
+                                                                @NotNull Project project,
+                                                                boolean physical) {
     final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByLanguage(fileType.getLanguage());
     if (profile != null) {
       return profile.createPatternTree(text, context, fileType, fileType.getLanguage(), null, project, physical);
@@ -30,15 +34,12 @@ public final class MatcherImplUtil {
     return PsiElement.EMPTY_ARRAY;
   }
 
-  public static PsiElement[] createTreeFromText(String text,
-                                                PatternContextInfo contextInfo,
-                                                LanguageFileType fileType,
-                                                Language language,
-                                                Project project,
-                                                boolean physical) {
-    if (language == null) {
-      language = fileType.getLanguage();
-    }
+  public static PsiElement @NotNull [] createTreeFromText(@NotNull String text,
+                                                          @NotNull PatternContextInfo contextInfo,
+                                                          @NotNull LanguageFileType fileType,
+                                                          @NotNull Language language,
+                                                          @NotNull Project project,
+                                                          boolean physical) {
     final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByLanguage(language);
     if (profile != null) {
       return profile.createPatternTree(text, contextInfo, fileType, language, project, physical);

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/XmlMatchingVisitor.java

@@ -12,6 +12,7 @@ import com.intellij.structuralsearch.impl.matcher.handlers.SubstitutionHandler;
 import com.intellij.structuralsearch.impl.matcher.iterators.ListNodeIterator;
 import com.intellij.structuralsearch.impl.matcher.iterators.SsrFilteringNodeIterator;
 import com.intellij.xml.util.XmlUtil;
+import org.jetbrains.annotations.NotNull;
 
 /**
 * @author Eugene.Kudelevsky
@@ -19,7 +20,7 @@ import com.intellij.xml.util.XmlUtil;
 public class XmlMatchingVisitor extends XmlElementVisitor {
   private final GlobalMatchingVisitor myMatchingVisitor;
 
-  public XmlMatchingVisitor(GlobalMatchingVisitor matchingVisitor) {
+  public XmlMatchingVisitor(@NotNull GlobalMatchingVisitor matchingVisitor) {
     myMatchingVisitor = matchingVisitor;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/CompileContext.java

@@ -5,6 +5,7 @@ import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.project.Project;
 import com.intellij.structuralsearch.MatchOptions;
 import com.intellij.structuralsearch.impl.matcher.CompiledPattern;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author maxim
@@ -16,7 +17,7 @@ public class CompileContext {
   private final MatchOptions myOptions;
   private final Project myProject;
 
-  public CompileContext(CompiledPattern pattern, MatchOptions options, Project project) {
+  public CompileContext(@NotNull CompiledPattern pattern, @NotNull MatchOptions options, @NotNull Project project) {
     myPattern = pattern;
     myOptions = options;
     myProject = project;
@@ -30,18 +31,22 @@ public class CompileContext {
     mySearchHelper.clear();
   }
 
+  @NotNull
   public OptimizingSearchHelper getSearchHelper() {
     return mySearchHelper;
   }
 
+  @NotNull
   public CompiledPattern getPattern() {
     return myPattern;
   }
 
+  @NotNull
   public MatchOptions getOptions() {
     return myOptions;
   }
 
+  @NotNull
   public Project getProject() {
     return myProject;
   }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/DeleteNodesAction.java

@@ -1,6 +1,7 @@
 package com.intellij.structuralsearch.impl.matcher.compiler;
 
 import com.intellij.psi.PsiElement;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
@@ -8,11 +9,11 @@ class DeleteNodesAction implements Runnable {
 
   private final List<? extends PsiElement> elements;
 
-  DeleteNodesAction(List<? extends PsiElement> _elements) {
+  DeleteNodesAction(@NotNull List<? extends PsiElement> _elements) {
     elements = _elements;
   }
 
-  private static void delete(PsiElement first, PsiElement last) {
+  private static void delete(@NotNull PsiElement first, PsiElement last) {
     if (last == first) {
       first.delete();
     }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/FindInFilesOptimizingSearchHelper.java

@@ -18,21 +18,21 @@ import static com.intellij.psi.search.UsageSearchContext.*;
  * @author Maxim.Mossienko
 */
 class FindInFilesOptimizingSearchHelper extends OptimizingSearchHelperBase {
-  private THashSet<VirtualFile> filesToScan;
-  private THashSet<VirtualFile> filesToScan2;
+  private Set<VirtualFile> filesToScan;
+  private Set<VirtualFile> filesToScan2;
 
   private final Project myProject;
   private final SearchScope myScope;
   private final boolean myCaseSensitive;
 
-  private boolean myTransactionStarted = false;
+  private boolean myTransactionStarted;
 
-  FindInFilesOptimizingSearchHelper(SearchScope scope, boolean caseSensitive, Project project) {
+  FindInFilesOptimizingSearchHelper(SearchScope scope, boolean caseSensitive, @NotNull Project project) {
     myScope = scope;
     myCaseSensitive = caseSensitive;
     myProject = project;
 
-    if (scope instanceof GlobalSearchScope && filesToScan == null) {
+    if (scope instanceof GlobalSearchScope) {
       filesToScan = new THashSet<>();
       filesToScan2 = new THashSet<>();
     }
@@ -90,7 +90,7 @@ class FindInFilesOptimizingSearchHelper extends OptimizingSearchHelperBase {
     if (!myTransactionStarted) return;
     myTransactionStarted = false;
     super.endTransaction();
-    final THashSet<VirtualFile> map = filesToScan;
+    Set<VirtualFile> map = filesToScan;
     if (!map.isEmpty()) map.clear();
     filesToScan = filesToScan2;
     filesToScan2 = map;
@@ -106,7 +106,7 @@ class FindInFilesOptimizingSearchHelper extends OptimizingSearchHelperBase {
     return filesToScan;
   }
 
-  private void process(VirtualFile[] files) {
+  private void process(VirtualFile @NotNull [] files) {
     if (scanRequest == 0) {
       Collections.addAll(filesToScan2, files);
     }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/GlobalCompilingVisitor.java

@@ -16,6 +16,7 @@ import com.intellij.structuralsearch.impl.matcher.predicates.RegExpPredicate;
 import com.intellij.util.SmartList;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
@@ -34,11 +35,12 @@ public class GlobalCompilingVisitor {
   private final List<PsiElement> myLexicalNodes = new SmartList<>();
   private int myCodeBlockLevel;
 
+  @NotNull
   public static NodeFilter getFilter() {
     return ourFilter;
   }
 
-  public void setHandler(PsiElement element, MatchingHandler handler) {
+  public void setHandler(@NotNull PsiElement element, @NotNull MatchingHandler handler) {
     MatchingHandler realHandler = context.getPattern().getHandlerSimple(element);
 
     if (realHandler instanceof SubstitutionHandler) {
@@ -50,7 +52,7 @@ public class GlobalCompilingVisitor {
     }
   }
 
-  public final void handle(PsiElement element) {
+  public final void handle(@NotNull PsiElement element) {
     if ((!ourFilter.accepts(element) ||
          StructuralSearchUtil.isIdentifier(element)) &&
         context.getPattern().isRealTypedVar(element) &&
@@ -83,7 +85,7 @@ public class GlobalCompilingVisitor {
     this.myCodeBlockLevel = codeBlockLevel;
   }
 
-  public static void setFilter(MatchingHandler handler, NodeFilter filter) {
+  public static void setFilter(@NotNull MatchingHandler handler, @NotNull NodeFilter filter) {
     if (handler.getFilter() != null && handler.getFilter().getClass() != filter.getClass()) {
       // for constructor we will have the same handler for class and method and tokens itself
       handler.setFilter(new CompositeNodeFilter(filter, handler.getFilter()));
@@ -93,19 +95,20 @@ public class GlobalCompilingVisitor {
     }
   }
 
-  public void setFilterSimple(PsiElement element, NodeFilter filter) {
+  public void setFilterSimple(@NotNull PsiElement element, @NotNull NodeFilter filter) {
     context.getPattern().getHandler(element).setFilter(filter);
   }
 
+  @NotNull
   public List<PsiElement> getLexicalNodes() {
     return myLexicalNodes;
   }
 
-  public void addLexicalNode(PsiElement node) {
+  public void addLexicalNode(@NotNull PsiElement node) {
     myLexicalNodes.add(node);
   }
 
-  void compile(PsiElement[] elements, CompileContext context) {
+  void compile(PsiElement @NotNull [] elements, @NotNull CompileContext context) {
     if (elements.length == 0) {
       throw new MalformedPatternException();
     }
@@ -119,17 +122,17 @@ public class GlobalCompilingVisitor {
     assert context.getPattern().getStrategy() != null;
   }
 
-  public boolean hasFragments(String pattern) {
+  public boolean hasFragments(@NotNull String pattern) {
     return ourSubstitutionPattern.matcher(pattern).find();
   }
 
   @Nullable
-  public MatchingHandler processPatternStringWithFragments(String pattern, OccurenceKind kind) {
+  public MatchingHandler processPatternStringWithFragments(@NotNull String pattern, @NotNull OccurenceKind kind) {
     return processPatternStringWithFragments(pattern, kind, ourSubstitutionPattern);
   }
 
   @Nullable
-  public MatchingHandler processPatternStringWithFragments(String pattern, OccurenceKind kind, Pattern substitutionPattern) {
+  public MatchingHandler processPatternStringWithFragments(@NotNull String pattern, @NotNull OccurenceKind kind, @NotNull Pattern substitutionPattern) {
     String content;
 
     if (kind == OccurenceKind.LITERAL) {
@@ -157,7 +160,7 @@ public class GlobalCompilingVisitor {
         hasLiteralContent = true;
         buf.append(StructuralSearchUtil.makeExtremeSpacesOptional(StructuralSearchUtil.shieldRegExpMetaChars(word)));
 
-        processTokenizedName(word, false, kind);
+        processTokenizedName(word, kind);
       }
 
       handler = (SubstitutionHandler)getContext().getPattern().getHandler(matcher.group(1));
@@ -174,7 +177,7 @@ public class GlobalCompilingVisitor {
       }
 
       if (isSuitablePredicate(predicate, handler)) {
-        processTokenizedName(predicate.getRegExp(), false, kind);
+        processTokenizedName(predicate.getRegExp(), kind);
       }
 
       start = matcher.end();
@@ -186,7 +189,7 @@ public class GlobalCompilingVisitor {
       hasLiteralContent = true;
       buf.append(StructuralSearchUtil.makeExtremeSpacesOptional(StructuralSearchUtil.shieldRegExpMetaChars(word)));
 
-      processTokenizedName(word, false, kind);
+      processTokenizedName(word, kind);
     }
 
     if (hasLiteralContent) {
@@ -206,14 +209,14 @@ public class GlobalCompilingVisitor {
   }
 
   @Contract("null,_ -> false")
-  public static boolean isSuitablePredicate(RegExpPredicate predicate, SubstitutionHandler handler) {
+  public static boolean isSuitablePredicate(RegExpPredicate predicate, @NotNull SubstitutionHandler handler) {
     return predicate != null && handler.getMinOccurs() != 0 && predicate.couldBeOptimized();
   }
 
-  public static void addFilesToSearchForGivenWord(String word,
+  public static void addFilesToSearchForGivenWord(@NotNull String word,
                                                   boolean endTransaction,
-                                                  GlobalCompilingVisitor.OccurenceKind kind,
-                                                  CompileContext compileContext) {
+                                                  @NotNull GlobalCompilingVisitor.OccurenceKind kind,
+                                                  @NotNull CompileContext compileContext) {
     if (!compileContext.getSearchHelper().doOptimizing()) {
       return;
     }
@@ -240,7 +243,7 @@ public class GlobalCompilingVisitor {
     }
   }
 
-  public void processTokenizedName(String name, boolean skipComments, GlobalCompilingVisitor.OccurenceKind kind) {
+  public void processTokenizedName(@NotNull String name, @NotNull GlobalCompilingVisitor.OccurenceKind kind) {
     if (kind == OccurenceKind.LITERAL) name = StringUtil.unescapeStringCharacters(name);
     for (String word : StringUtil.getWordsInStringLongestFirst(name)) {
       addFilesToSearchForGivenWord(word, true, kind, getContext());

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/OptimizingSearchHelper.java

@@ -13,13 +13,13 @@ public interface OptimizingSearchHelper {
   boolean doOptimizing();
   void clear();
 
-  void addWordToSearchInCode(String word);
+  void addWordToSearchInCode(@NotNull String word);
 
-  void addWordToSearchInText(String word);
+  void addWordToSearchInText(@NotNull String word);
 
-  void addWordToSearchInComments(String word);
+  void addWordToSearchInComments(@NotNull String word);
 
-  void addWordToSearchInLiterals(String word);
+  void addWordToSearchInLiterals(@NotNull String word);
 
   void endTransaction();
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/OptimizingSearchHelperBase.java

@@ -4,24 +4,18 @@ package com.intellij.structuralsearch.impl.matcher.compiler;
 import gnu.trove.THashSet;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Set;
+
 /**
  * @author Maxim.Mossienko
 */
 abstract class OptimizingSearchHelperBase implements OptimizingSearchHelper {
-  private final THashSet<String> scanned;
-  private final THashSet<String> scannedText;
-  private final THashSet<String> scannedComments;
-  private final THashSet<String> scannedLiterals;
+  private final Set<String> scanned = new THashSet<>();
+  private final Set<String> scannedText = new THashSet<>();
+  private final Set<String> scannedComments = new THashSet<>();
+  private final Set<String> scannedLiterals = new THashSet<>();
   protected int scanRequest;
 
-  OptimizingSearchHelperBase() {
-    scanRequest = 0;
-    scanned = new THashSet<>();
-    scannedText = new THashSet<>();
-    scannedComments = new THashSet<>();
-    scannedLiterals = new THashSet<>();
-  }
-
   @Override
   public void clear() {
     scanned.clear();
@@ -31,29 +25,29 @@ abstract class OptimizingSearchHelperBase implements OptimizingSearchHelper {
   }
 
   @Override
-  public void addWordToSearchInCode(String word) {
-    if (word != null && doOptimizing() && scanned.add(word)) {
+  public void addWordToSearchInCode(@NotNull String word) {
+    if (doOptimizing() && scanned.add(word)) {
       doAddSearchWordInCode(word);
     }
   }
 
   @Override
-  public void addWordToSearchInText(String word) {
-    if (word != null && doOptimizing() && scannedText.add(word)) {
+  public void addWordToSearchInText(@NotNull String word) {
+    if (doOptimizing() && scannedText.add(word)) {
       doAddSearchWordInText(word);
     }
   }
 
   @Override
-  public void addWordToSearchInComments(String word) {
-    if (word != null && doOptimizing() && scannedComments.add(word)) {
+  public void addWordToSearchInComments(@NotNull String word) {
+    if (doOptimizing() && scannedComments.add(word)) {
       doAddSearchWordInComments(word);
     }
   }
 
   @Override
-  public void addWordToSearchInLiterals(String word) {
-    if (word != null && doOptimizing() && scannedLiterals.add(word)) {
+  public void addWordToSearchInLiterals(@NotNull String word) {
+    if (doOptimizing() && scannedLiterals.add(word)) {
       doAddSearchWordInLiterals(word);
     }
   }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/PatternCompiler.java

@@ -56,7 +56,7 @@ public final class PatternCompiler {
   }
 
   @Nullable
-  private static CompiledPattern doCompilePattern(Project project, MatchOptions options,
+  private static CompiledPattern doCompilePattern(@NotNull Project project, @NotNull MatchOptions options,
                                                   boolean checkForErrors, boolean optimizeScope)
     throws MalformedPatternException, NoMatchFoundException {
 
@@ -84,7 +84,8 @@ public final class PatternCompiler {
         optimizeScope(options, checkForErrors, context, result);
       }
       return result;
-    } finally {
+    }
+    finally {
       context.clear();
     }
   }
@@ -176,10 +177,10 @@ public final class PatternCompiler {
   }
 
   @NotNull
-  private static List<PsiElement> compileByAllPrefixes(Project project,
-                                                       MatchOptions options,
-                                                       CompiledPattern pattern,
-                                                       CompileContext context,
+  private static List<PsiElement> compileByAllPrefixes(@NotNull Project project,
+                                                       @NotNull MatchOptions options,
+                                                       @NotNull CompiledPattern pattern,
+                                                       @NotNull CompileContext context,
                                                        String @NotNull [] applicablePrefixes,
                                                        boolean checkForErrors) throws MalformedPatternException {
     if (applicablePrefixes.length == 0) {
@@ -396,11 +397,12 @@ public final class PatternCompiler {
     }
   }
 
-  private static List<PsiElement> doCompile(Project project,
-                                            MatchOptions options,
-                                            CompiledPattern result,
-                                            PrefixProvider prefixProvider,
-                                            CompileContext context,
+  @NotNull
+  private static List<PsiElement> doCompile(@NotNull Project project,
+                                            @NotNull MatchOptions options,
+                                            @NotNull CompiledPattern result,
+                                            @NotNull PrefixProvider prefixProvider,
+                                            @NotNull CompileContext context,
                                             boolean checkForErrors) throws MalformedPatternException {
     result.clearHandlers();
 
@@ -524,7 +526,8 @@ public final class PatternCompiler {
 
         addExtensionPredicates(options, constraint, handler);
         addScriptConstraint(project, Configuration.CONTEXT_VAR_NAME, constraint, handler, variableNames, options, checkForErrors);
-      } catch (MalformedPatternException e) {
+      }
+      catch (MalformedPatternException e) {
         if (checkForErrors) throw e;
       }
     }
@@ -564,7 +567,7 @@ public final class PatternCompiler {
     return elements;
   }
 
-  private static void addExtensionPredicates(MatchOptions options, MatchVariableConstraint constraint, SubstitutionHandler handler) {
+  private static void addExtensionPredicates(@NotNull MatchOptions options, @NotNull MatchVariableConstraint constraint, @NotNull SubstitutionHandler handler) {
     final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByFileType(options.getFileType());
     assert profile != null;
     for (MatchPredicate matchPredicate : profile.getCustomPredicates(constraint, handler.getName(), options)) {

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/StringToConstraintsTransformer.java

@@ -29,10 +29,11 @@ public final class StringToConstraintsTransformer {
   @NonNls private static final String WITHIN = "within";
   @NonNls private static final String CONTEXT = "context";
 
-  private static final Set<String> knownOptions = ContainerUtil.set(REF, REGEX, REGEXW, EXPRTYPE, FORMAL, SCRIPT, CONTAINS, WITHIN, CONTEXT);
+  private static final Set<String> knownOptions =
+    ContainerUtil.set(REF, REGEX, REGEXW, EXPRTYPE, FORMAL, SCRIPT, CONTAINS, WITHIN, CONTEXT);
 
   @SuppressWarnings("AssignmentToForLoopParameter")
-  public static void transformCriteria(@NotNull String criteria, MatchOptions options) {
+  public static void transformCriteria(@NotNull String criteria, @NotNull MatchOptions options) {
     final StringBuilder pattern = new StringBuilder();
     int anonymousTypedVarsCount = 0;
     boolean targetFound = false;
@@ -40,7 +41,7 @@ public final class StringToConstraintsTransformer {
     final MatchVariableConstraint context = options.addNewVariableConstraint(Configuration.CONTEXT_VAR_NAME);
 
     final int length = criteria.length();
-    for(int index = 0; index < length; ++index) {
+    for (int index = 0; index < length; ++index) {
       char ch = criteria.charAt(index);
 
       if (index == 0 && ch == '[') {
@@ -51,7 +52,7 @@ public final class StringToConstraintsTransformer {
       if (ch == '\\' && index + 1 < length) {
         ch = criteria.charAt(++index);
       }
-      else if (ch=='\'') {
+      else if (ch == '\'') {
         final int newIndex = handleCharacterLiteral(criteria, index, pattern);
         if (newIndex != index) {
           index = newIndex;
@@ -65,14 +66,15 @@ public final class StringToConstraintsTransformer {
 
         boolean target = true;
         final String typedVar;
-        if (criteria.charAt(index)=='_')  {
+        if (criteria.charAt(index) == '_') {
           target = false;
 
-          if(endIndex == index + 1) {
+          if (endIndex == index + 1) {
             // anonymous var, make it unique for the case of constraints
             anonymousTypedVarsCount++;
             typedVar = "_" + anonymousTypedVarsCount;
-          } else {
+          }
+          else {
             typedVar = criteria.substring(index + 1, endIndex);
           }
         }
@@ -100,14 +102,17 @@ public final class StringToConstraintsTransformer {
           if (ch == '+') {
             maxOccurs = Integer.MAX_VALUE;
             ++index;
-          } else if (ch == '?') {
+          }
+          else if (ch == '?') {
             minOccurs = 0;
             ++index;
-          } else if (ch == '*') {
+          }
+          else if (ch == '*') {
             minOccurs = 0;
             maxOccurs = Integer.MAX_VALUE;
             ++index;
-          } else if (ch == '{') {
+          }
+          else if (ch == '{') {
             ++index;
             minOccurs = -1;
             maxOccurs = -1;
@@ -118,7 +123,7 @@ public final class StringToConstraintsTransformer {
               ++index;
             }
 
-            if (ch==',') {
+            if (ch == ',') {
               ++index;
 
               while (index < length && (ch = criteria.charAt(index)) >= '0' && ch <= '9') {
@@ -127,25 +132,36 @@ public final class StringToConstraintsTransformer {
                 if (maxOccurs < 0) throw new MalformedPatternException(SSRBundle.message("error.overflow"));
                 ++index;
               }
-            } else {
+            }
+            else {
               maxOccurs = -2;
             }
 
             if (ch != '}') {
               if (minOccurs < 0 && maxOccurs < 0) throw new MalformedPatternException(SSRBundle.message("error.expected.digit"));
-              if (maxOccurs < 0) throw new MalformedPatternException(SSRBundle.message("error.expected.brace1"));
-              else throw new MalformedPatternException(SSRBundle.message("error.expected.brace2"));
+              if (maxOccurs < 0) {
+                throw new MalformedPatternException(SSRBundle.message("error.expected.brace1"));
+              }
+              else {
+                throw new MalformedPatternException(SSRBundle.message("error.expected.brace2"));
+              }
+            }
+            if (minOccurs < 0 && maxOccurs < 0) {
+              throw new MalformedPatternException(SSRBundle.message("error.empty.quantifier"));
+            }
+            else if (minOccurs == -1) {
+              minOccurs = 0;
+            }
+            else if (maxOccurs == -1) {
+              maxOccurs = Integer.MAX_VALUE;
             }
-            if (minOccurs < 0 && maxOccurs < 0) throw new MalformedPatternException(SSRBundle.message("error.empty.quantifier"));
-            else if (minOccurs == -1) minOccurs = 0;
-            else if (maxOccurs == -1) maxOccurs = Integer.MAX_VALUE;
             else if (maxOccurs == -2) maxOccurs = minOccurs;
             ++index;
           }
 
           if (index < length) {
             ch = criteria.charAt(index);
-            if (ch=='?') {
+            if (ch == '?') {
               greedy = false;
               ++index;
             }
@@ -175,8 +191,9 @@ public final class StringToConstraintsTransformer {
             pattern.append(ch);
           }
           else {
-            if (!constraintCreated)
+            if (!constraintCreated) {
               throw new MalformedPatternException(SSRBundle.message("error.condition.only.on.first.variable.reference"));
+            }
             index = handleTypedVarCondition(index, criteria, constraint);
           }
         }
@@ -197,21 +214,27 @@ public final class StringToConstraintsTransformer {
     options.setSearchPattern(pattern.toString());
   }
 
-  public static int handleCharacterLiteral(String criteria, int index, StringBuilder pattern) {
+  public static int handleCharacterLiteral(@NotNull String criteria, int index, @NotNull StringBuilder pattern) {
     final int length = criteria.length();
     if (index + 1 < length && criteria.charAt(index + 1) == '\'') {
       // ignore next '
       pattern.append('\'');
       return index + 1;
-    } else if (index + 2 < length && criteria.charAt(index + 2) == '\'') {
+    }
+    else if (index + 2 < length && criteria.charAt(index + 2) == '\'') {
       // eat simple character
       pattern.append(criteria, index, index + 3);
       return index + 2;
-    } else if (index + 3 < length && criteria.charAt(index + 1) == '\\' && criteria.charAt(index + 3) == '\'') {
+    }
+    else if (index + 3 < length && criteria.charAt(index + 1) == '\\' && criteria.charAt(index + 3) == '\'') {
       // eat simple escape character
       pattern.append(criteria, index, index + 4);
       return index + 3;
-    } else if (index + 7 < length && criteria.charAt(index + 1) == '\\' && criteria.charAt(index + 2) == 'u' && criteria.charAt(index + 7) == '\'') {
+    }
+    else if (index + 7 < length &&
+             criteria.charAt(index + 1) == '\\' &&
+             criteria.charAt(index + 2) == 'u' &&
+             criteria.charAt(index + 7) == '\'') {
       // eat unicode escape character
       pattern.append(criteria, index, index + 8);
       return index + 7;
@@ -219,7 +242,7 @@ public final class StringToConstraintsTransformer {
     return index;
   }
 
-  private static int handleTypedVarCondition(int index, String criteria, MatchVariableConstraint constraint) {
+  private static int handleTypedVarCondition(int index, @NotNull String criteria, @NotNull MatchVariableConstraint constraint) {
     final int length = criteria.length();
 
     char ch = criteria.charAt(index);
@@ -231,7 +254,7 @@ public final class StringToConstraintsTransformer {
     }
     if (ch == '+' || ch == '*') {
       // this is type axis navigation relation
-      switch(ch) {
+      switch (ch) {
         case '+':
           constraint.setStrictlyWithinHierarchy(true);
           break;
@@ -252,7 +275,9 @@ public final class StringToConstraintsTransformer {
       while (++endIndex < length) {
         if (criteria.charAt(endIndex - 1) != '\\') {
           ch = criteria.charAt(endIndex);
-          if (ch == '"') quoted = !quoted;
+          if (ch == '"') {
+            quoted = !quoted;
+          }
           else if (ch == ']' && !quoted) break;
         }
       }
@@ -267,7 +292,7 @@ public final class StringToConstraintsTransformer {
     }
   }
 
-  private static int handleRegExp(int index, String criteria, MatchVariableConstraint constraint) {
+  private static int handleRegExp(int index, @NotNull String criteria, @NotNull MatchVariableConstraint constraint) {
     final int length = criteria.length();
     int endIndex = index;
     while (endIndex < length && !Character.isWhitespace(criteria.charAt(endIndex))) {
@@ -275,8 +300,12 @@ public final class StringToConstraintsTransformer {
     }
 
     if (endIndex == index) {
-      if (criteria.charAt(index - 1) == ':') throw new MalformedPatternException(SSRBundle.message("error.expected.condition", ":"));
-      else return endIndex;
+      if (criteria.charAt(index - 1) == ':') {
+        throw new MalformedPatternException(SSRBundle.message("error.expected.condition", ":"));
+      }
+      else {
+        return endIndex;
+      }
     }
     final String regexp = criteria.substring(index, endIndex);
 
@@ -292,7 +321,7 @@ public final class StringToConstraintsTransformer {
   }
 
   @SuppressWarnings("AssignmentToForLoopParameter")
-  private static void parseCondition(MatchVariableConstraint constraint, String condition) {
+  private static void parseCondition(@NotNull MatchVariableConstraint constraint, @NotNull String condition) {
     final int length = condition.length();
     final StringBuilder text = new StringBuilder();
     boolean invert = false;
@@ -319,7 +348,9 @@ public final class StringToConstraintsTransformer {
         while (++i < length) {
           c = condition.charAt(i);
           if (condition.charAt(i - 1) != '\\') {
-            if (c == '"') quoted = !quoted;
+            if (c == '"') {
+              quoted = !quoted;
+            }
             else if (c == ')' && !quoted) {
               int j = 1;
               while (j <= spaces && condition.charAt(i - j) == ' ') j++;
@@ -333,8 +364,10 @@ public final class StringToConstraintsTransformer {
         }
         if (text.length() == 0) throw new MalformedPatternException(SSRBundle.message("error.argument.expected", option));
         if (quoted) throw new MalformedPatternException(SSRBundle.message("error.expected.value", "\""));
-        if (!closed) throw new MalformedPatternException(SSRBundle.message("error.expected.value",
-                                                                           StringUtil.repeatSymbol(' ', spaces) + ")"));
+        if (!closed) {
+          throw new MalformedPatternException(SSRBundle.message("error.expected.value",
+                                                                StringUtil.repeatSymbol(' ', spaces) + ")"));
+        }
         handleOption(constraint, option, text.toString(), invert);
         text.setLength(0);
         invert = false;
@@ -345,8 +378,9 @@ public final class StringToConstraintsTransformer {
           handleOption(constraint, text.toString(), "", invert);
           optionExpected = false;
         }
-        if (++i == length || condition.charAt(i) != '&' || optionExpected)
+        if (++i == length || condition.charAt(i) != '&' || optionExpected) {
           throw new MalformedPatternException(SSRBundle.message("error.unexpected.value", "&"));
+        }
         text.setLength(0);
         invert = false;
         optionExpected = true;
@@ -365,7 +399,9 @@ public final class StringToConstraintsTransformer {
     if (text.length() != 0) {
       handleOption(constraint, text.toString(), "", invert);
     }
-    else if (invert) throw new MalformedPatternException(SSRBundle.message("error.expected.condition", "!"));
+    else if (invert) {
+      throw new MalformedPatternException(SSRBundle.message("error.expected.condition", "!"));
+    }
     else if (optionExpected) throw new MalformedPatternException(SSRBundle.message("error.expected.condition", length == 0 ? "[" : "&&"));
   }
 
@@ -415,15 +451,17 @@ public final class StringToConstraintsTransformer {
       constraint.setInvertContainsConstraint(invert);
     }
     else if (option.equals(WITHIN)) {
-      if (!Configuration.CONTEXT_VAR_NAME.equals(constraint.getName()))
+      if (!Configuration.CONTEXT_VAR_NAME.equals(constraint.getName())) {
         throw new MalformedPatternException(SSRBundle.message("error.only.applicable.to.complete.match", option));
+      }
       constraint.setWithinConstraint(argument);
       constraint.setInvertWithinConstraint(invert);
     }
     else if (option.equals(CONTEXT)) {
       if (invert) throw new MalformedPatternException(SSRBundle.message("error.cannot.invert", option));
-      if (!Configuration.CONTEXT_VAR_NAME.equals(constraint.getName()))
+      if (!Configuration.CONTEXT_VAR_NAME.equals(constraint.getName())) {
         throw new MalformedPatternException(SSRBundle.message("error.only.applicable.to.complete.match", option));
+      }
       constraint.setContextConstraint(argument);
     }
     else if (option.startsWith("_")) {
@@ -444,7 +482,8 @@ public final class StringToConstraintsTransformer {
     }
   }
 
-  private static String unescape(String s) {
+  @NotNull
+  private static String unescape(@NotNull String s) {
     final StringBuilder result = new StringBuilder();
     boolean escaped = false;
     for (int i = 0, length = s.length(); i < length; i++) {

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/TestModeOptimizingSearchHelper.java

@@ -14,7 +14,7 @@ import java.util.Set;
  */
 class TestModeOptimizingSearchHelper extends OptimizingSearchHelperBase {
   private final StringBuilder builder = new StringBuilder();
-  private boolean myTransactionStarted = false;
+  private boolean myTransactionStarted;
 
   private final List<String> myWords = new SmartList<>();
 
@@ -23,7 +23,7 @@ class TestModeOptimizingSearchHelper extends OptimizingSearchHelperBase {
     return true;
   }
 
-  private void append(final String word, final String prefix) {
+  private void append(@NotNull String word, @NotNull String prefix) {
     myWords.add(prefix + word);
     myTransactionStarted = true;
   }
@@ -77,6 +77,7 @@ class TestModeOptimizingSearchHelper extends OptimizingSearchHelperBase {
     return Collections.emptySet();
   }
 
+  @NotNull
   public String getSearchPlan() {
     assert !myTransactionStarted;
     final String plan = builder.toString();

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/WordOptimizer.java

@@ -6,6 +6,7 @@ import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.structuralsearch.impl.matcher.CompiledPattern;
 import com.intellij.structuralsearch.impl.matcher.handlers.SubstitutionHandler;
 import com.intellij.structuralsearch.impl.matcher.predicates.RegExpPredicate;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.Collections;
@@ -69,7 +70,8 @@ public interface WordOptimizer {
    * @param className  the name of the class to search for subclasses of
    * @param includeSelf  include the class itself in the search
    */
-  default List<String> getDescendantsOf(String className, boolean includeSelf, Project project) {
+  @NotNull
+  default List<String> getDescendantsOf(@NotNull String className, boolean includeSelf, @NotNull Project project) {
     return Collections.emptyList();
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/compiler/XmlCompilingVisitor.java

@@ -20,14 +20,15 @@ import static com.intellij.structuralsearch.impl.matcher.compiler.GlobalCompilin
 * @author Eugene.Kudelevsky
 */
 public class XmlCompilingVisitor extends XmlRecursiveElementVisitor {
-  final GlobalCompilingVisitor myCompilingVisitor;
+  @NotNull
+  private final GlobalCompilingVisitor myCompilingVisitor;
   private final XmlWordOptimizer myOptimizer = new XmlWordOptimizer();
 
-  public XmlCompilingVisitor(GlobalCompilingVisitor compilingVisitor) {
+  public XmlCompilingVisitor(@NotNull GlobalCompilingVisitor compilingVisitor) {
     this.myCompilingVisitor = compilingVisitor;
   }
 
-  public void compile(PsiElement[] topLevelElements) {
+  public void compile(PsiElement @NotNull [] topLevelElements) {
     final CompileContext context = myCompilingVisitor.getContext();
     final CompiledPattern pattern = context.getPattern();
     final MatchOptions options = context.getOptions();
@@ -39,12 +40,11 @@ public class XmlCompilingVisitor extends XmlRecursiveElementVisitor {
     }
   }
 
-  public void optimize(PsiElement element) {
+  public void optimize(@NotNull PsiElement element) {
     element.accept(myOptimizer);
   }
 
   private class XmlWordOptimizer extends XmlRecursiveElementWalkingVisitor implements WordOptimizer {
-
     @Override
     public void visitXmlTag(XmlTag tag) {
       if (!handleWord(tag.getName(), CODE, myCompilingVisitor.getContext())) return;

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/filters/CompositeNodeFilter.java

@@ -2,19 +2,20 @@ package com.intellij.structuralsearch.impl.matcher.filters;
 
 import com.intellij.dupLocator.util.NodeFilter;
 import com.intellij.psi.PsiElement;
+import org.jetbrains.annotations.NotNull;
 
 public class CompositeNodeFilter implements NodeFilter {
   private final NodeFilter first;
   private final NodeFilter second;
 
+  public CompositeNodeFilter(@NotNull NodeFilter _first, @NotNull NodeFilter _second) {
+    first = _first;
+    second = _second;
+  }
+
   @Override
   public boolean accepts(PsiElement element) {
     return first.accepts(element) ||
            second.accepts(element);
   }
-
-  public CompositeNodeFilter(NodeFilter _first, NodeFilter _second) {
-    first = _first;
-    second = _second;
-  }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/filters/DefaultFilter.java

@@ -3,12 +3,14 @@ package com.intellij.structuralsearch.impl.matcher.filters;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.impl.source.tree.LeafElement;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 /**
  * Default searching filter
  */
 public final class DefaultFilter {
-  public static boolean accepts(PsiElement patternNode, PsiElement matchNode) {
+  public static boolean accepts(@NotNull PsiElement patternNode, @Nullable PsiElement matchNode) {
     if (patternNode instanceof LeafElement && matchNode instanceof LeafElement) {
       return ((LeafElement)patternNode).getElementType() == ((LeafElement)matchNode).getElementType();
     }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/filters/LexicalNodesFilter.java

@@ -11,7 +11,7 @@ import com.intellij.structuralsearch.StructuralSearchUtil;
  */
 public final class LexicalNodesFilter implements NodeFilter {
 
-  LexicalNodesFilter() {}
+  private LexicalNodesFilter() {}
 
   public static NodeFilter getInstance() {
     return NodeFilterHolder.INSTANCE;

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/LightTopLevelMatchingHandler.java

@@ -14,22 +14,22 @@ public final class LightTopLevelMatchingHandler extends MatchingHandler implemen
   }
 
   @Override
-  public boolean match(final PsiElement patternNode, final PsiElement matchedNode, final MatchContext matchContext) {
+  public boolean match(final PsiElement patternNode, final PsiElement matchedNode, final @NotNull MatchContext matchContext) {
     return myDelegate.match(patternNode, matchedNode, matchContext);
   }
 
   @Override
-  public boolean canMatch(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean canMatch(@NotNull PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     return myDelegate.canMatch(patternNode, matchedNode, context);
   }
 
   @Override
-  public boolean matchSequentially(final NodeIterator patternNodes, final NodeIterator matchNodes, final MatchContext context) {
+  public boolean matchSequentially(final @NotNull NodeIterator patternNodes, final @NotNull NodeIterator matchNodes, final @NotNull MatchContext context) {
     return myDelegate.matchSequentially(patternNodes, matchNodes, context);
   }
 
   @Override
-  public boolean isMatchSequentiallySucceeded(final NodeIterator matchNodes) {
+  public boolean isMatchSequentiallySucceeded(final @NotNull NodeIterator matchNodes) {
     return true;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/LiteralWithSubstitutionHandler.java

@@ -3,6 +3,7 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 import java.util.regex.Matcher;
@@ -21,11 +22,11 @@ public class LiteralWithSubstitutionHandler extends MatchingHandler {
   }
 
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     return match(matchedNode, matchedNode.getText(), 0, context);
   }
 
-  public boolean match(PsiElement matchedNode, String text, int textOffset, MatchContext context) {
+  public boolean match(@NotNull PsiElement matchedNode, @NotNull String text, int textOffset, @NotNull MatchContext context) {
     if (myMatcher == null) {
       myMatcher = Pattern.compile(myRegexp, (myCaseSensitive ? 0 : Pattern.CASE_INSENSITIVE) | Pattern.DOTALL).matcher(text);
     }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/MatchingHandler.java

@@ -13,6 +13,7 @@ import com.intellij.structuralsearch.impl.matcher.MatchResultImpl;
 import com.intellij.structuralsearch.impl.matcher.filters.DefaultFilter;
 import com.intellij.structuralsearch.impl.matcher.strategies.MatchingStrategy;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.HashSet;
 import java.util.Set;
@@ -28,9 +29,8 @@ public abstract class MatchingHandler {
   /**
    * Node filters determine which kind of PsiElements can match the pattern element.
    * Filters are applied to MatchingHandlers in the CompilingVisitor.
-   * @param filter
    */
-  public void setFilter(NodeFilter filter) {
+  public void setFilter(@Nullable NodeFilter filter) {
     this.filter = filter;
   }
 
@@ -40,15 +40,15 @@ public abstract class MatchingHandler {
    * @param context of the matching
    * @return true if matching was successful and false otherwise
    */
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     return (patternNode == null) ? matchedNode == null : canMatch(patternNode, matchedNode, context);
   }
 
-  public boolean canMatch(final PsiElement patternNode, final PsiElement matchedNode, MatchContext context) {
+  public boolean canMatch(@NotNull PsiElement patternNode, final PsiElement matchedNode, @NotNull MatchContext context) {
     return (filter != null) ? filter.accepts(matchedNode) : DefaultFilter.accepts(patternNode, matchedNode);
   }
 
-  public boolean matchSequentially(NodeIterator patternNodes, NodeIterator matchNodes, MatchContext context) {
+  public boolean matchSequentially(@NotNull NodeIterator patternNodes, @NotNull NodeIterator matchNodes, @NotNull MatchContext context) {
     final MatchingStrategy strategy = context.getPattern().getStrategy();
     final PsiElement currentPatternNode = patternNodes.current();
     final PsiElement currentMatchNode = matchNodes.current();
@@ -89,18 +89,18 @@ public abstract class MatchingHandler {
     return false;
   }
 
-  private static void skipComments(NodeIterator matchNodes, PsiElement patternNode) {
+  private static void skipComments(@NotNull NodeIterator matchNodes, PsiElement patternNode) {
     if (patternNode instanceof PsiComment) return;
     while (matchNodes.current() instanceof PsiComment) matchNodes.advance();
   }
 
-  private static void skipIfNecessary(NodeIterator nodes, PsiElement elementToMatchWith, MatchingStrategy strategy) {
+  private static void skipIfNecessary(@NotNull NodeIterator nodes, PsiElement elementToMatchWith, @NotNull MatchingStrategy strategy) {
     while (nodes.hasNext() && strategy.shouldSkip(nodes.current(), elementToMatchWith)) {
       nodes.advance();
     }
   }
 
-  protected boolean isMatchSequentiallySucceeded(final NodeIterator matchNodes) {
+  protected boolean isMatchSequentiallySucceeded(@NotNull NodeIterator matchNodes) {
     skipComments(matchNodes, null);
     return !matchNodes.hasNext();
   }
@@ -112,7 +112,8 @@ public abstract class MatchingHandler {
       super(true);
     }
 
-    @Override public void visitElement(@NotNull PsiElement element) {
+    @Override
+    public void visitElement(@NotNull PsiElement element) {
       // We do not reset certain handlers because they are also bound to higher level nodes
       // e.g. Identifier handler in name is also bound to PsiMethod
       if (pattern.isToResetHandler(element)) {
@@ -124,7 +125,7 @@ public abstract class MatchingHandler {
       super.visitElement(element);
     }
 
-    synchronized void clearState(CompiledPattern _pattern, PsiElement el) {
+    synchronized void clearState(@NotNull CompiledPattern _pattern, @NotNull PsiElement el) {
       pattern = _pattern;
       el.acceptChildren(this);
       pattern = null;
@@ -133,7 +134,7 @@ public abstract class MatchingHandler {
 
   protected static ClearStateVisitor clearingVisitor = new ClearStateVisitor();
 
-  public boolean matchInAnyOrder(NodeIterator patternNodes, NodeIterator matchedNodes, final MatchContext context) {
+  public static boolean matchInAnyOrder(@NotNull NodeIterator patternNodes, @NotNull NodeIterator matchedNodes, @NotNull MatchContext context) {
     final MatchResultImpl saveResult = context.hasResult() ? context.getResult() : null;
     context.setResult(null);
 
@@ -207,7 +208,7 @@ public abstract class MatchingHandler {
     }
   }
 
-  protected static boolean validateSatisfactionOfHandlers(NodeIterator patternNodes, MatchContext context) {
+  protected static boolean validateSatisfactionOfHandlers(@NotNull NodeIterator patternNodes, @NotNull MatchContext context) {
     for (; patternNodes.hasNext(); patternNodes.advance()) {
       if (!context.getPattern().getHandler(patternNodes.current()).validate(context, 0)) {
         return false;
@@ -216,7 +217,7 @@ public abstract class MatchingHandler {
     return true;
   }
 
-  boolean validate(MatchContext context, int matchedOccurs) {
+  boolean validate(@NotNull MatchContext context, int matchedOccurs) {
     return matchedOccurs == 1;
   }
 
@@ -224,7 +225,7 @@ public abstract class MatchingHandler {
     return filter;
   }
 
-  public boolean shouldAdvanceThePatternFor(PsiElement patternElement, PsiElement matchedElement) {
+  public boolean shouldAdvanceThePatternFor(@NotNull PsiElement patternElement, @NotNull PsiElement matchedElement) {
     return true;
   }
 
@@ -240,7 +241,7 @@ public abstract class MatchingHandler {
     return pinnedElement;
   }
 
-  public void setPinnedElement(final PsiElement pinnedElement) {
+  public void setPinnedElement(@NotNull PsiElement pinnedElement) {
     this.pinnedElement = pinnedElement;
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/SimpleHandler.java

@@ -3,6 +3,7 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Handles simplest type of the match: one node from the pattern to one node of the code.
@@ -15,7 +16,7 @@ public final class SimpleHandler extends MatchingHandler {
    * @return true if matching was successful and false otherwise
    */
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     if (!super.match(patternNode, matchedNode, context)) return false;
     return context.getMatcher().match(patternNode, matchedNode);
   }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/SkippingHandler.java

@@ -24,7 +24,7 @@ public class SkippingHandler extends MatchingHandler implements DelegatingHandle
   }
 
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, final MatchContext matchContext) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, final @NotNull MatchContext matchContext) {
     if (patternNode == null || matchedNode == null || matchedNode.getClass() == patternNode.getClass()) {
       return myDelegate.match(patternNode, matchedNode, matchContext);
     }
@@ -43,7 +43,7 @@ public class SkippingHandler extends MatchingHandler implements DelegatingHandle
   }
 
   @Override
-  public boolean canMatch(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean canMatch(@NotNull PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     final PsiElement newPatternNode = skipNodeIfNecessary(patternNode);
     if (newPatternNode != patternNode) {
       return context.getPattern().getHandler(newPatternNode).canMatch(newPatternNode, matchedNode, context);
@@ -52,12 +52,12 @@ public class SkippingHandler extends MatchingHandler implements DelegatingHandle
   }
 
   @Override
-  public boolean matchSequentially(final NodeIterator patternNodes, final NodeIterator matchNodes, final MatchContext context) {
+  public boolean matchSequentially(final @NotNull NodeIterator patternNodes, final @NotNull NodeIterator matchNodes, final @NotNull MatchContext context) {
     return myDelegate.matchSequentially(patternNodes, matchNodes, context);
   }
 
   @Override
-  protected boolean isMatchSequentiallySucceeded(final NodeIterator matchNodes) {
+  protected boolean isMatchSequentiallySucceeded(final @NotNull NodeIterator matchNodes) {
     return myDelegate.isMatchSequentiallySucceeded(matchNodes);
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/SubstitutionHandler.java

@@ -27,6 +27,7 @@ import java.util.List;
  * Matching handler that manages substitutions matching
  */
 public class SubstitutionHandler extends MatchingHandler {
+  @NotNull
   private final String name;
   private final int maxOccurs;
   private final int minOccurs;
@@ -40,25 +41,22 @@ public class SubstitutionHandler extends MatchingHandler {
   private int matchedOccurs;
   private int totalMatchedOccurs = -1;
   private MatchResultImpl myNestedResult;
-  private boolean myRepeatedVar = false;
+  private boolean myRepeatedVar;
 
-  private static final NodeFilter VARS_DELIM_FILTER = new NodeFilter() {
-    @Override
-    public boolean accepts(PsiElement element) {
-      if (element == null) {
-        return false;
-      }
-
-      final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByPsiElement(element);
-      if (profile == null) {
-        return false;
-      }
-
-      return profile.canBeVarDelimiter(element);
+  private static final NodeFilter VARS_DELIM_FILTER = element -> {
+    if (element == null) {
+      return false;
     }
+
+    final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByPsiElement(element);
+    if (profile == null) {
+      return false;
+    }
+
+    return profile.canBeVarDelimiter(element);
   };
 
-  public SubstitutionHandler(String name, boolean target, int minOccurs, int maxOccurs, boolean greedy) {
+  public SubstitutionHandler(@NotNull String name, boolean target, int minOccurs, int maxOccurs, boolean greedy) {
     if (minOccurs < 0) throw new IllegalArgumentException("minOccurs must be greater or equal to 0");
     if (minOccurs > maxOccurs) throw new IllegalArgumentException("maxOccurs must be greater equal to minOccurs");
     this.name = name;
@@ -117,30 +115,25 @@ public class SubstitutionHandler extends MatchingHandler {
     return null;
   }
 
-  private boolean validateOneMatch(PsiElement match, int start, int end, MatchResult result, MatchContext matchContext) {
+  private boolean validateOneMatch(@NotNull PsiElement match, int start, int end, @NotNull MatchResult result, @NotNull MatchContext matchContext) {
     if (!myRepeatedVar) {
       return true;
     }
-    if (match != null) {
-      if (start == 0 && end == -1 && result.getStart() == 0 && result.getEnd() == -1) {
-        return matchContext.getMatcher().match(match, result.getMatch());
-      }
-      else {
-        final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByPsiElement(match);
-        assert profile != null;
-        return profile.getText(match, start, end).equals(result.getMatchImage());
-      }
+    if (start == 0 && end == -1 && result.getStart() == 0 && result.getEnd() == -1) {
+      return matchContext.getMatcher().match(match, result.getMatch());
     }
     else {
-      return result.getMatchImage() == null;
+      final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByPsiElement(match);
+      assert profile != null;
+      return profile.getText(match, start, end).equals(result.getMatchImage());
     }
   }
 
-  public boolean validate(PsiElement match, MatchContext context) {
+  public boolean validate(PsiElement match, @NotNull MatchContext context) {
     return validate(match, 0, -1, context);
   }
 
-  public boolean validate(PsiElement match, int start, int end, MatchContext context) {
+  public boolean validate(PsiElement match, int start, int end, @NotNull MatchContext context) {
     if (match == null || predicate != null && !predicate.match(match, start, end, context)) {
       return false;
     }
@@ -158,7 +151,8 @@ public class SubstitutionHandler extends MatchingHandler {
       if (minOccurs == 1 && maxOccurs == 1) {
         // check if they are the same
         return validateOneMatch(match, start, end, result,context);
-      } else if (maxOccurs > 1 && totalMatchedOccurs != -1) {
+      }
+      if (maxOccurs > 1 && totalMatchedOccurs != -1) {
         if (result.isMultipleMatch()) {
           final List<MatchResult> children = result.getChildren();
           final int size = children.size();
@@ -178,7 +172,7 @@ public class SubstitutionHandler extends MatchingHandler {
   }
 
   @Override
-  public boolean match(PsiElement node, PsiElement match, MatchContext context) {
+  public boolean match(PsiElement node, PsiElement match, @NotNull MatchContext context) {
     if (!super.match(node, match, context)) return false;
 
     return matchHandler == null ?
@@ -186,11 +180,11 @@ public class SubstitutionHandler extends MatchingHandler {
            matchHandler.match(node, match, context);
   }
 
-  public void addResult(@NotNull PsiElement match, MatchContext context) {
+  public void addResult(@NotNull PsiElement match, @NotNull MatchContext context) {
     addResult(match, 0, -1, context);
   }
 
-  public void addResult(@NotNull PsiElement match, int start, int end, MatchContext context) {
+  public void addResult(@NotNull PsiElement match, int start, int end, @NotNull MatchContext context) {
     if (totalMatchedOccurs == -1) {
       final MatchResultImpl matchResult = context.getResult();
       final MatchResultImpl substitution = matchResult.findChild(name);
@@ -231,11 +225,11 @@ public class SubstitutionHandler extends MatchingHandler {
     }
   }
 
-  public boolean handle(PsiElement match, MatchContext context) {
+  public boolean handle(PsiElement match, @NotNull MatchContext context) {
     return handle(match, 0, -1, context);
   }
 
-  public boolean handle(PsiElement match, int start, int end, MatchContext context) {
+  public boolean handle(PsiElement match, int start, int end, @NotNull MatchContext context) {
     if (!validate(match, start, end, context)) {
       myNestedResult = null;
       
@@ -247,11 +241,14 @@ public class SubstitutionHandler extends MatchingHandler {
       return false;
     }
 
-    if (!Configuration.CONTEXT_VAR_NAME.equals(name)) addResult(match, start, end, context);
+    if (!Configuration.CONTEXT_VAR_NAME.equals(name)) {
+      addResult(match, start, end, context);
+    }
 
     return true;
   }
 
+  @NotNull
   private MatchResultImpl createMatch(@NotNull PsiElement match, int start, int end) {
     final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByPsiElement(match);
     assert profile != null;
@@ -268,12 +265,12 @@ public class SubstitutionHandler extends MatchingHandler {
     ) : myNestedResult;
 
     if (myNestedResult != null) {
-      myNestedResult.setName( name );
-      myNestedResult.setMatchImage( image );
-      myNestedResult.setMatchRef( ref );
-      myNestedResult.setStart( start );
-      myNestedResult.setEnd( end );
-      myNestedResult.setTarget( target );
+      myNestedResult.setName(name);
+      myNestedResult.setMatchImage(image);
+      myNestedResult.setMatchRef(ref);
+      myNestedResult.setStart(start);
+      myNestedResult.setEnd(end);
+      myNestedResult.setTarget(target);
       myNestedResult = null;
     }
 
@@ -281,7 +278,7 @@ public class SubstitutionHandler extends MatchingHandler {
   }
 
   @Override
-  boolean validate(MatchContext context, int matchedOccurs) {
+  boolean validate(@NotNull MatchContext context, int matchedOccurs) {
     if (minOccurs > matchedOccurs) return false;
     if (maxOccurs < matchedOccurs) return false;
     return true;
@@ -295,7 +292,7 @@ public class SubstitutionHandler extends MatchingHandler {
     return maxOccurs;
   }
 
-  private void removeLastResults(int numberOfResults, MatchContext context) {
+  private void removeLastResults(int numberOfResults, @NotNull MatchContext context) {
     if (numberOfResults == 0) return;
     final MatchResultImpl substitution = context.getResult().findChild(name);
 
@@ -318,11 +315,11 @@ public class SubstitutionHandler extends MatchingHandler {
   }
 
   @Override
-  public boolean matchSequentially(NodeIterator patternNodes, NodeIterator matchNodes, MatchContext context) {
+  public boolean matchSequentially(@NotNull NodeIterator patternNodes, @NotNull NodeIterator matchNodes, @NotNull MatchContext context) {
     return doMatchSequentially(patternNodes, matchNodes, context);
   }
 
-  protected boolean doMatchSequentiallyBySimpleHandler(NodeIterator patternNodes, NodeIterator matchNodes, MatchContext context) {
+  protected boolean doMatchSequentiallyBySimpleHandler(NodeIterator patternNodes, NodeIterator matchNodes, @NotNull MatchContext context) {
     final boolean oldValue = context.shouldRecursivelyMatch();
     context.setShouldRecursivelyMatch(false);
     final boolean result = super.matchSequentially(patternNodes, matchNodes, context);
@@ -330,7 +327,9 @@ public class SubstitutionHandler extends MatchingHandler {
     return result;
   }
 
-  protected boolean doMatchSequentially(NodeIterator patternNodes, NodeIterator matchNodes, MatchContext context) {
+  protected boolean doMatchSequentially(@NotNull NodeIterator patternNodes,
+                                        @NotNull NodeIterator matchNodes,
+                                        @NotNull MatchContext context) {
     final int previousMatchedOccurs = matchedOccurs;
     final FilteringNodeIterator fNodes = new FilteringNodeIterator(matchNodes, VARS_DELIM_FILTER);
 
@@ -345,9 +344,10 @@ public class SubstitutionHandler extends MatchingHandler {
       while (fNodes.hasNext() && matchedOccurs < minOccurs) {
         if (handler.match(currentPatternNode, matchNodes.current(), context)) {
           ++matchedOccurs;
-        } else if (handler instanceof TopLevelMatchingHandler && matchedOccurs == 0 ||
-                   currentPatternNode instanceof PsiComment ||
-                   !(matchNodes.current() instanceof PsiComment)) {
+        }
+        else if (handler instanceof TopLevelMatchingHandler && matchedOccurs == 0 ||
+                 currentPatternNode instanceof PsiComment ||
+                 !(matchNodes.current() instanceof PsiComment)) {
           break;
         }
         fNodes.advance();
@@ -361,15 +361,16 @@ public class SubstitutionHandler extends MatchingHandler {
         return false;
       }
 
-      if (greedy)  {
+      if (greedy) {
         // go greedily to maxOccurs
 
         while (fNodes.hasNext() && matchedOccurs < maxOccurs) {
           if (handler.match(currentPatternNode, matchNodes.current(), context)) {
             ++matchedOccurs;
-          } else if (handler instanceof TopLevelMatchingHandler && matchedOccurs == 0 ||
-                     currentPatternNode instanceof PsiComment ||
-                     !(matchNodes.current() instanceof PsiComment)) {
+          }
+          else if (handler instanceof TopLevelMatchingHandler && matchedOccurs == 0 ||
+                   currentPatternNode instanceof PsiComment ||
+                   !(matchNodes.current() instanceof PsiComment)) {
             break;
           }
           fNodes.advance();
@@ -404,7 +405,8 @@ public class SubstitutionHandler extends MatchingHandler {
             removeLastResults(matchedOccurs, context);
           }
           patternNodes.rewind();
-        } else {
+        }
+        else {
           // match found
           if (handler.isMatchSequentiallySucceeded(matchNodes)) {
             return checkSameOccurrencesConstraint(context);
@@ -412,7 +414,8 @@ public class SubstitutionHandler extends MatchingHandler {
           removeLastResults(matchedOccurs, context);
         }
         return false;
-      } else {
+      }
+      else {
         patternNodes.advance();
 
         if (flag) {
@@ -437,7 +440,8 @@ public class SubstitutionHandler extends MatchingHandler {
 
             if (handler.match(patternNodes.current(), matchNodes.current(), context)) {
               matchedOccurs++;
-            } else {
+            }
+            else {
               patternNodes.rewind();
               removeLastResults(matchedOccurs, context);
               return false;
@@ -449,16 +453,18 @@ public class SubstitutionHandler extends MatchingHandler {
           patternNodes.rewind();
           removeLastResults(matchedOccurs, context);
           return false;
-        } else {
+        }
+        else {
           return checkSameOccurrencesConstraint(context);
         }
       }
-    } finally {
+    }
+    finally {
       matchedOccurs = previousMatchedOccurs;
     }
   }
 
-  private boolean checkSameOccurrencesConstraint(MatchContext context) {
+  private boolean checkSameOccurrencesConstraint(@NotNull MatchContext context) {
     if (totalMatchedOccurs == -1) {
       totalMatchedOccurs = matchedOccurs;
       return true;
@@ -474,7 +480,7 @@ public class SubstitutionHandler extends MatchingHandler {
     this.target = target;
   }
 
-  public void setMatchHandler(MatchingHandler matchHandler) {
+  public void setMatchHandler(@NotNull MatchingHandler matchHandler) {
     this.matchHandler = matchHandler;
   }
 
@@ -482,7 +488,7 @@ public class SubstitutionHandler extends MatchingHandler {
     return target;
   }
 
-  public String getName() {
+  public @NotNull String getName() {
     return name;
   }
 
@@ -493,7 +499,7 @@ public class SubstitutionHandler extends MatchingHandler {
   }
 
   @Override
-  public boolean shouldAdvanceThePatternFor(PsiElement patternElement, PsiElement matchedElement) {
+  public boolean shouldAdvanceThePatternFor(@NotNull PsiElement patternElement, @NotNull PsiElement matchedElement) {
     if(maxOccurs > 1) return false;
     return super.shouldAdvanceThePatternFor(patternElement,matchedElement);
   }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/SymbolHandler.java

@@ -3,6 +3,7 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Search handler for symbol search
@@ -15,7 +16,7 @@ public class SymbolHandler extends MatchingHandler {
   }
 
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     return handler.handle(matchedNode, context);
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/TopLevelMatchingHandler.java

@@ -19,7 +19,7 @@ public final class TopLevelMatchingHandler extends MatchingHandler implements De
   }
 
   @Override
-  public boolean match(final PsiElement patternNode, final PsiElement matchedNode, final MatchContext matchContext) {
+  public boolean match(final PsiElement patternNode, final PsiElement matchedNode, final @NotNull MatchContext matchContext) {
     final boolean matched = delegate.match(patternNode, matchedNode, matchContext);
 
     if (matched) {
@@ -48,17 +48,17 @@ public final class TopLevelMatchingHandler extends MatchingHandler implements De
   }
 
   @Override
-  public boolean canMatch(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean canMatch(@NotNull PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     return delegate.canMatch(patternNode, matchedNode, context);
   }
 
   @Override
-  public boolean matchSequentially(final NodeIterator patternNodes, final NodeIterator matchNodes, final MatchContext context) {
+  public boolean matchSequentially(final @NotNull NodeIterator patternNodes, final @NotNull NodeIterator matchNodes, final @NotNull MatchContext context) {
     return delegate.matchSequentially(patternNodes, matchNodes, context);
   }
 
   @Override
-  public boolean isMatchSequentiallySucceeded(final NodeIterator matchNodes) {
+  public boolean isMatchSequentiallySucceeded(final @NotNull NodeIterator matchNodes) {
     return true;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/TypedSymbolHandler.java

@@ -2,13 +2,14 @@ package com.intellij.structuralsearch.impl.matcher.handlers;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Search handler for typed symbol ('T<a*>)
  */
 public class TypedSymbolHandler extends MatchingHandler {
   @Override
-  public boolean match(PsiElement patternNode, PsiElement matchedNode, MatchContext context) {
+  public boolean match(PsiElement patternNode, PsiElement matchedNode, @NotNull MatchContext context) {
     if (!super.match(patternNode,matchedNode,context)) {
       return false;
     }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/AndPredicate.java

@@ -17,18 +17,19 @@ package com.intellij.structuralsearch.impl.matcher.predicates;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 public final class AndPredicate extends MatchPredicate {
   private final MatchPredicate first;
   private final MatchPredicate second;
 
-  public AndPredicate(MatchPredicate first, MatchPredicate second) {
+  public AndPredicate(@NotNull MatchPredicate first, @NotNull MatchPredicate second) {
     this.first = first;
     this.second = second;
   }
 
   @Override
-  public boolean match(PsiElement matchedNode, int start, int end, MatchContext context) {
+  public boolean match(@NotNull PsiElement matchedNode, int start, int end, @NotNull MatchContext context) {
     return first.match(matchedNode, start, end, context) && second.match(matchedNode, start, end, context);
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/ContainsPredicate.java

@@ -2,6 +2,7 @@ package com.intellij.structuralsearch.impl.matcher.predicates;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Maxim.Mossienko
@@ -12,7 +13,7 @@ public class ContainsPredicate extends MatchPredicate {
   }
 
   @Override
-  public boolean match(PsiElement match, int start, int end, MatchContext context) {
+  public boolean match(@NotNull PsiElement match, int start, int end, @NotNull MatchContext context) {
     return false;
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/MatchPredicate.java

@@ -17,6 +17,7 @@ package com.intellij.structuralsearch.impl.matcher.predicates;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 public abstract class MatchPredicate {
   /**
@@ -25,9 +26,9 @@ public abstract class MatchPredicate {
    * @param context of the matching
    * @return true if matching was successful, false otherwise
    */
-  public abstract boolean match(PsiElement matchedNode, int start, int end, MatchContext context);
+  public abstract boolean match(@NotNull PsiElement matchedNode, int start, int end, @NotNull MatchContext context);
 
-  public final boolean match(PsiElement matchedNode, MatchContext context) {
+  public final boolean match(@NotNull PsiElement matchedNode, @NotNull MatchContext context) {
     return match(matchedNode, 0, -1, context);
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/NotPredicate.java

@@ -17,6 +17,7 @@ package com.intellij.structuralsearch.impl.matcher.predicates;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Negates predicate
@@ -24,12 +25,12 @@ import com.intellij.structuralsearch.impl.matcher.MatchContext;
 public final class NotPredicate extends MatchPredicate {
   private final MatchPredicate myPredicate;
 
-  public NotPredicate(final MatchPredicate predicate) {
+  public NotPredicate(@NotNull MatchPredicate predicate) {
     myPredicate = predicate;
   }
 
   @Override
-  public boolean match(PsiElement matchedNode, int start, int end, MatchContext context) {
+  public boolean match(@NotNull PsiElement matchedNode, int start, int end, @NotNull MatchContext context) {
     return !myPredicate.match(matchedNode, start, end, context);
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/ReferencePredicate.java

@@ -9,6 +9,7 @@ import com.intellij.psi.PsiReferenceService;
 import com.intellij.structuralsearch.Matcher;
 import com.intellij.structuralsearch.StructuralSearchUtil;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 import java.util.Objects;
@@ -20,12 +21,12 @@ public final class ReferencePredicate extends MatchPredicate {
 
   private final Matcher matcher;
 
-  public ReferencePredicate(String constraint, LanguageFileType fileType, Project project) {
+  public ReferencePredicate(@NotNull String constraint, @NotNull LanguageFileType fileType, @NotNull Project project) {
     matcher = Matcher.buildMatcher(project, fileType, constraint);
   }
 
   @Override
-  public boolean match(PsiElement matchedNode, int start, int end, MatchContext context) {
+  public boolean match(@NotNull PsiElement matchedNode, int start, int end, @NotNull MatchContext context) {
     matchedNode = StructuralSearchUtil.getParentIfIdentifier(matchedNode);
     final List<PsiReference> references = PsiReferenceService.getService().getReferences(matchedNode, PsiReferenceService.Hints.NO_HINTS);
     return references.stream().map(PsiReference::resolve).filter(Objects::nonNull).anyMatch(t -> matcher.matchNode(t));

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/RegExpPredicate.java

@@ -1,7 +1,7 @@
 // Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.structuralsearch.impl.matcher.predicates;
 
-import com.intellij.psi.*;
+import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.MalformedPatternException;
 import com.intellij.structuralsearch.SSRBundle;
 import com.intellij.structuralsearch.StructuralSearchUtil;
@@ -9,6 +9,7 @@ import com.intellij.structuralsearch.impl.matcher.MatchContext;
 import com.intellij.structuralsearch.impl.matcher.MatchResultImpl;
 import com.intellij.structuralsearch.plugin.util.SmartPsiPointer;
 import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -19,6 +20,7 @@ public final class RegExpPredicate extends MatchPredicate {
   private final String baseHandlerName;
   private boolean simpleString;
   private final boolean couldBeOptimized;
+  @NotNull
   private final String regexp;
   private final boolean caseSensitive;
   private boolean multiline;
@@ -30,7 +32,7 @@ public final class RegExpPredicate extends MatchPredicate {
     String getText(PsiElement element);
   }
 
-  public RegExpPredicate(String regexp, boolean caseSensitive, String _baseHandlerName, boolean _wholeWords, boolean _target) {
+  public RegExpPredicate(@NotNull String regexp, boolean caseSensitive, String _baseHandlerName, boolean _wholeWords, boolean _target) {
     couldBeOptimized = !StructuralSearchUtil.containsRegExpMetaChar(regexp);
     if (!_wholeWords) {
       simpleString = couldBeOptimized;
@@ -54,8 +56,9 @@ public final class RegExpPredicate extends MatchPredicate {
         realRegexp = ".*?\\b(?:" + realRegexp + ")\\b.*?";
       }
 
-      pattern = Pattern.compile(realRegexp, (caseSensitive ? 0: Pattern.CASE_INSENSITIVE) | (multiline ? Pattern.DOTALL:0));
-    } catch(PatternSyntaxException ex) {
+      pattern = Pattern.compile(realRegexp, (caseSensitive ? 0 : Pattern.CASE_INSENSITIVE) | (multiline ? Pattern.DOTALL : 0));
+    }
+    catch (PatternSyntaxException ex) {
       throw new MalformedPatternException(SSRBundle.message("error.incorrect.regexp.constraint", regexp, baseHandlerName));
     }
   }
@@ -64,6 +67,7 @@ public final class RegExpPredicate extends MatchPredicate {
     return couldBeOptimized;
   }
 
+  @NotNull
   public String getRegExp() {
     return regexp;
   }
@@ -75,9 +79,7 @@ public final class RegExpPredicate extends MatchPredicate {
    * @return true if matching was successful and false otherwise
    */
   @Override
-  public boolean match(PsiElement matchedNode, int start, int end, MatchContext context) {
-    if (matchedNode==null) return false;
-
+  public boolean match(@NotNull PsiElement matchedNode, int start, int end, @NotNull MatchContext context) {
     final String text = myNodeTextGenerator != null
                         ? myNodeTextGenerator.getText(matchedNode)
                         : StructuralSearchUtil.getMeaningfulText(matchedNode);
@@ -94,11 +96,11 @@ public final class RegExpPredicate extends MatchPredicate {
     return result;
   }
 
-  public boolean doMatch(String text, MatchContext context, PsiElement matchedElement) {
+  public boolean doMatch(@NotNull String text, @NotNull MatchContext context, @NotNull PsiElement matchedElement) {
     return doMatch(text, 0, -1 ,context, matchedElement);
   }
 
-  boolean doMatch(String text, int from, int end, MatchContext context,PsiElement matchedElement) {
+  private boolean doMatch(@NotNull String text, int from, int end, @NotNull MatchContext context, @NotNull PsiElement matchedElement) {
     if (from > 0 || end != -1) {
       text = text.substring(from, (end == -1 || end >= text.length()) ? text.length() : end);
     }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/ScriptPredicate.java

@@ -5,6 +5,7 @@ import com.intellij.openapi.project.Project;
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.MatchOptions;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.Set;
 
@@ -19,9 +20,7 @@ public class ScriptPredicate extends MatchPredicate {
   }
 
   @Override
-  public boolean match(PsiElement match, int start, int end, MatchContext context) {
-    if (match == null) return false;
-
+  public boolean match(@NotNull PsiElement match, int start, int end, @NotNull MatchContext context) {
     return Boolean.TRUE.equals(scriptSupport.evaluate(context.hasResult() ? context.getResult() : null, match));
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/ScriptSupport.java

@@ -91,7 +91,7 @@ public class ScriptSupport {
 
   public Object evaluate(MatchResult result, PsiElement context) {
     try {
-      final HashMap<String, Object> variableMap = new HashMap<>();
+      Map<String, Object> variableMap = new HashMap<>();
       myVariableNames.forEach(n -> variableMap.put(n, null));
       variableMap.put(ScriptLog.SCRIPT_LOG_VAR_NAME, myScriptLog);
       if (result != null) {

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/predicates/WithinPredicate.java

@@ -8,6 +8,7 @@ import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.structuralsearch.MatchResult;
 import com.intellij.structuralsearch.Matcher;
 import com.intellij.structuralsearch.impl.matcher.MatchContext;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
@@ -18,12 +19,12 @@ public class WithinPredicate extends MatchPredicate {
 
   private final Matcher matcher;
 
-  public WithinPredicate(String within, LanguageFileType fileType, Project project) {
+  public WithinPredicate(@NotNull String within, @NotNull LanguageFileType fileType, @NotNull Project project) {
     matcher = Matcher.buildMatcher(project, fileType, within);
   }
 
   @Override
-  public boolean match(PsiElement matchedNode, int start, int end, MatchContext context) {
+  public boolean match(@NotNull PsiElement matchedNode, int start, int end, @NotNull MatchContext context) {
     final List<MatchResult> results = matcher.matchByDownUp(matchedNode);
     for (MatchResult result : results) {
       if (PsiTreeUtil.isAncestor(result.getMatch(), matchedNode, false)) {

platform/structuralsearch/source/com/intellij/structuralsearch/inspection/InspectionProfileUtil.java

@@ -8,6 +8,7 @@ import com.intellij.codeInspection.ex.InspectionToolWrapper;
 import com.intellij.openapi.project.Project;
 import com.intellij.profile.codeInspection.ui.SingleInspectionProfilePanel;
 import com.intellij.util.ui.UIUtil;
+import org.jetbrains.annotations.NotNull;
 
 import java.awt.*;
 
@@ -18,19 +19,20 @@ public final class InspectionProfileUtil {
 
   private InspectionProfileUtil() {}
 
-  public static SSBasedInspection getStructuralSearchInspection(InspectionProfile profile) {
+  @NotNull
+  public static SSBasedInspection getStructuralSearchInspection(@NotNull InspectionProfile profile) {
     final InspectionToolWrapper<?, ?> wrapper = profile.getInspectionTool(SSBasedInspection.SHORT_NAME, (Project)null);
     assert wrapper != null;
     return (SSBasedInspection)wrapper.getTool();
   }
 
-  public static InspectionProfileModifiableModel getInspectionProfile(Component c) {
+  public static InspectionProfileModifiableModel getInspectionProfile(@NotNull Component c) {
     final SingleInspectionProfilePanel panel = UIUtil.uiParents(c, true).filter(SingleInspectionProfilePanel.class).first();
     if (panel == null) return null;
     return panel.getProfile();
   }
 
-  public static void fireProfileChanged(InspectionProfileImpl profile) {
+  public static void fireProfileChanged(@NotNull InspectionProfileImpl profile) {
     profile.getProfileManager().fireProfileChanged(profile);
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/inspection/SSBasedInspection.java

@@ -39,12 +39,12 @@ import java.util.*;
 import java.util.stream.Collectors;
 
 public class SSBasedInspection extends LocalInspectionTool implements DynamicGroupTool {
-  static final Object LOCK = new Object(); // hack to avoid race conditions in SSR
+  private static final Object LOCK = ObjectUtils.sentinel("SSRLock"); // hack to avoid race conditions in SSR
 
   @NonNls public static final String SHORT_NAME = "SSBasedInspection";
   private final List<Configuration> myConfigurations = ContainerUtil.createLockFreeCopyOnWriteList();
-  final Set<String> myProblemsReported = new HashSet<>(1);
-  private InspectionProfileImpl mySessionProfile = null;
+  private final Set<String> myProblemsReported = new HashSet<>(1);
+  private InspectionProfileImpl mySessionProfile;
 
   @Override
   public void writeSettings(@NotNull Element node) throws WriteExternalException {
@@ -154,7 +154,7 @@ public class SSBasedInspection extends LocalInspectionTool implements DynamicGro
     };
   }
 
-  public static void register(Configuration configuration) {
+  public static void register(@NotNull Configuration configuration) {
     if (configuration.getOrder() != 0) {
       // not a main configuration containing meta data
       return;
@@ -175,7 +175,7 @@ public class SSBasedInspection extends LocalInspectionTool implements DynamicGro
     }
   }
 
-  private static boolean isMetaDataChanged(Configuration configuration, HighlightDisplayKey key) {
+  private static boolean isMetaDataChanged(@NotNull Configuration configuration, @NotNull HighlightDisplayKey key) {
     if (StringUtil.isEmpty(configuration.getSuppressId())) {
       if (!SHORT_NAME.equals(key.getID())) return true;
     }
@@ -184,14 +184,14 @@ public class SSBasedInspection extends LocalInspectionTool implements DynamicGro
   }
 
   @Override
-  public List<LocalInspectionToolWrapper> getChildren() {
+  public @NotNull List<LocalInspectionToolWrapper> getChildren() {
     return getConfigurations().stream()
       .filter(configuration -> configuration.getOrder() == 0)
       .map(configuration -> new StructuralSearchInspectionToolWrapper(getConfigurationsWithUuid(configuration.getUuid())))
       .collect(Collectors.toList());
   }
 
-  static LocalQuickFix createQuickFix(final Project project, final MatchResult matchResult, final Configuration configuration) {
+  private static LocalQuickFix createQuickFix(@NotNull Project project, @NotNull MatchResult matchResult, @NotNull Configuration configuration) {
     if (!(configuration instanceof ReplaceConfiguration)) return null;
     final ReplaceConfiguration replaceConfiguration = (ReplaceConfiguration)configuration;
     final Replacer replacer = new Replacer(project, replaceConfiguration.getReplaceOptions());
@@ -221,7 +221,8 @@ public class SSBasedInspection extends LocalInspectionTool implements DynamicGro
     };
   }
 
-  private Configuration getMainConfiguration(Configuration configuration) {
+  @NotNull
+  private Configuration getMainConfiguration(@NotNull Configuration configuration) {
     if (configuration.getOrder() == 0) {
       return configuration;
     }
@@ -229,10 +230,12 @@ public class SSBasedInspection extends LocalInspectionTool implements DynamicGro
     return myConfigurations.stream().filter(c -> c.getOrder() == 0 && uuid.equals(c.getUuid())).findFirst().orElse(configuration);
   }
 
+  @NotNull
   public List<Configuration> getConfigurations() {
     return Collections.unmodifiableList(myConfigurations);
   }
 
+  @NotNull
   public List<Configuration> getConfigurationsWithUuid(@NotNull UUID uuid) {
     final List<Configuration> configurations = ContainerUtil.filter(myConfigurations, c -> uuid.equals(c.getUuid()));
     configurations.sort(Comparator.comparingInt(Configuration::getOrder));
@@ -267,13 +270,13 @@ public class SSBasedInspection extends LocalInspectionTool implements DynamicGro
     private final Configuration myConfiguration;
     private PairProcessor<? super MatchResult, ? super Configuration> myProcessor;
 
-    InspectionResultSink(PairProcessor<? super MatchResult, ? super Configuration> processor, Configuration configuration) {
+    InspectionResultSink(@NotNull PairProcessor<? super MatchResult, ? super Configuration> processor, @NotNull Configuration configuration) {
       myProcessor = processor;
       myConfiguration = configuration;
     }
 
     @Override
-    public void newMatch(MatchResult result) {
+    public void newMatch(@NotNull MatchResult result) {
       myProcessor.process(result, myConfiguration);
     }
 

platform/structuralsearch/source/com/intellij/structuralsearch/inspection/SSBasedInspectionCompiledPatternsCache.java

@@ -25,7 +25,6 @@ import java.util.Map;
  * @author Eugene.Kudelevsky
  */
 final class SSBasedInspectionCompiledPatternsCache {
-
   private static final Logger LOG = Logger.getInstance(SSBasedInspectionCompiledPatternsCache.class);
   private static final Key<Map<Configuration, Matcher>> COMPILED_OPTIONS_KEY = Key.create("SSR_INSPECTION_COMPILED_OPTIONS_KEY");
   private final Project myProject;
@@ -43,13 +42,15 @@ final class SSBasedInspectionCompiledPatternsCache {
   }
 
   @NotNull
-  Map<Configuration, Matcher> getCompiledOptions(@NotNull List<Configuration> configurations) {
+  Map<Configuration, Matcher> getCompiledOptions(@NotNull List<? extends Configuration> configurations) {
     final Map<Configuration, Matcher> cache = getCompiledOptions(configurations, myProject.getUserData(COMPILED_OPTIONS_KEY));
     myProject.putUserData(COMPILED_OPTIONS_KEY, cache);
     return cache;
   }
 
-  Map<Configuration, Matcher> getCompiledOptions(@NotNull List<Configuration> configurations, @Nullable Map<Configuration, Matcher> cache) {
+  @NotNull
+  private Map<Configuration, Matcher> getCompiledOptions(@NotNull List<? extends Configuration> configurations,
+                                                         @Nullable Map<Configuration, Matcher> cache) {
     if (areConfigurationsInCache(configurations, cache)) {
       return cache;
     }
@@ -79,7 +80,7 @@ final class SSBasedInspectionCompiledPatternsCache {
   }
 
   @Contract("_, null -> false")
-  private static boolean areConfigurationsInCache(List<Configuration> configurations, @Nullable Map<Configuration, Matcher> cache) {
+  private static boolean areConfigurationsInCache(@NotNull List<? extends Configuration> configurations, @Nullable Map<Configuration, Matcher> cache) {
     return cache != null && configurations.size() == cache.size() && configurations.stream().allMatch(key -> cache.containsKey(key));
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/inspection/StructuralSearchFakeInspection.java

@@ -115,10 +115,10 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
   }
 
   @Override
-  public @Nullable JComponent createOptionsPanel() {
+  public @NotNull JComponent createOptionsPanel() {
     final MyListModel model = new MyListModel();
     final JButton button = new JButton(SSRBundle.message("edit.metadata.button"));
-    button.addActionListener(e -> performEditMetaData(button));
+    button.addActionListener(__ -> performEditMetaData(button));
 
     final JList<Configuration> list = new JBList<>(model);
     list.setCellRenderer(new ConfigurationCellRenderer());
@@ -148,7 +148,7 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
     return panel;
   }
 
-  private void performEditMetaData(Component context) {
+  private void performEditMetaData(@NotNull Component context) {
     final Project project = CommonDataKeys.PROJECT.getData(DataManager.getInstance().getDataContext(context));
     final InspectionProfileModifiableModel profile = InspectionProfileUtil.getInspectionProfile(context);
     if (profile == null) {
@@ -170,7 +170,7 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
     InspectionProfileUtil.fireProfileChanged(profile);
   }
 
-  private void performMove(JList<Configuration> list, boolean up) {
+  private void performMove(@NotNull JList<Configuration> list, boolean up) {
     final MyListModel model = (MyListModel)list.getModel();
     final List<Configuration> values = list.getSelectedValuesList();
     final Comparator<Configuration> c = Comparator.comparingInt(Configuration::getOrder);
@@ -195,7 +195,8 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
     profile.setModified(true);
   }
 
-  private static Configuration moveMetaData(Configuration source, Configuration target) {
+  @NotNull
+  private static Configuration moveMetaData(@NotNull Configuration source, @NotNull Configuration target) {
     if (source == target) return source;
     target.setDescription(source.getDescription());
     target.setSuppressId(source.getSuppressId());
@@ -206,7 +207,7 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
     return target;
   }
 
-  private void performAdd(JList<Configuration> list, AnActionButton b) {
+  private void performAdd(@NotNull JList<Configuration> list, @NotNull AnActionButton b) {
     final AnAction[] children = new AnAction[]{new AddTemplateAction(list, false), new AddTemplateAction(list, true)};
     final RelativePoint point = b.getPreferredPopupPoint();
     if (point == null) return;
@@ -215,7 +216,7 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
                                                         JBPopupFactory.ActionSelectionAid.SPEEDSEARCH, true).show(point);
   }
 
-  private void performRemove(JList<Configuration> list) {
+  private void performRemove(@NotNull JList<Configuration> list) {
     boolean metaData = false;
     for (Configuration configuration : list.getSelectedValuesList()) {
       if (configuration.getOrder() == 0) {
@@ -250,7 +251,7 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
     profile.setModified(true);
   }
 
-  private void performEdit(JList<Configuration> list) {
+  private void performEdit(@NotNull JList<Configuration> list) {
     final Project project = CommonDataKeys.PROJECT.getData(DataManager.getInstance().getDataContext(list));
     if (project == null) return;
     final int index = list.getSelectedIndex();
@@ -278,11 +279,11 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
   }
 
   private final class AddTemplateAction extends DumbAwareAction {
-
+    @NotNull
     private final JList<Configuration> myList;
     private final boolean myReplace;
 
-    private AddTemplateAction(JList<Configuration> list, boolean replace) {
+    private AddTemplateAction(@NotNull JList<Configuration> list, boolean replace) {
       super(replace
             ? SSRBundle.message("SSRInspection.add.replace.template.button")
             : SSRBundle.message("SSRInspection.add.search.template.button"));
@@ -326,7 +327,6 @@ public class StructuralSearchFakeInspection extends LocalInspectionTool {
   }
 
   private class MyListModel extends AbstractListModel<Configuration> {
-
     @Override
     public int getSize() {
       return myConfigurations.size();

platform/structuralsearch/source/com/intellij/structuralsearch/inspection/StructuralSearchProfileActionProvider.java

@@ -48,7 +48,7 @@ public class StructuralSearchProfileActionProvider extends InspectionProfileActi
 
   @NotNull
   @Override
-  public List<AnAction> getActions(SingleInspectionProfilePanel panel) {
+  public List<AnAction> getActions(@NotNull SingleInspectionProfilePanel panel) {
     final InspectionProfileModifiableModel profile = panel.getProfile();
     if (profile.getToolsOrNull(SSBasedInspection.SHORT_NAME, null) != null &&
         !profile.isToolEnabled(HighlightDisplayKey.find(SSBasedInspection.SHORT_NAME))) {
@@ -76,10 +76,9 @@ public class StructuralSearchProfileActionProvider extends InspectionProfileActi
   }
 
   private static final class RemoveInspectionAction extends DumbAwareAction {
-
     private final SingleInspectionProfilePanel myPanel;
 
-    private RemoveInspectionAction(SingleInspectionProfilePanel panel) {
+    private RemoveInspectionAction(@NotNull SingleInspectionProfilePanel panel) {
       super(SSRBundle.message("remove.inspection.button"), null, AllIcons.General.Remove);
       myPanel = panel;
       registerCustomShortcutSet(CommonShortcuts.getDelete(), myPanel);
@@ -104,11 +103,10 @@ public class StructuralSearchProfileActionProvider extends InspectionProfileActi
   }
 
   private static final class AddInspectionAction extends DumbAwareAction {
-
     private final SingleInspectionProfilePanel myPanel;
     private final boolean myReplace;
 
-    private AddInspectionAction(SingleInspectionProfilePanel panel, boolean replace) {
+    private AddInspectionAction(@NotNull SingleInspectionProfilePanel panel, boolean replace) {
       super(replace
             ? SSRBundle.message("SSRInspection.add.replace.template.button")
             : SSRBundle.message("SSRInspection.add.search.template.button"));
@@ -138,9 +136,9 @@ public class StructuralSearchProfileActionProvider extends InspectionProfileActi
     createNewInspection(configuration, project, InspectionProfileManager.getInstance(project).getCurrentProfile());
   }
 
-  static boolean createNewInspection(@NotNull Configuration configuration,
-                                     @NotNull Project project,
-                                     @NotNull InspectionProfileImpl profile) {
+  private static boolean createNewInspection(@NotNull Configuration configuration,
+                                             @NotNull Project project,
+                                             @NotNull InspectionProfileImpl profile) {
     final SSBasedInspection inspection = InspectionProfileUtil.getStructuralSearchInspection(profile);
     if (!ApplicationManager.getApplication().isUnitTestMode()) {
       configuration.setOrder(0); // reset
@@ -159,7 +157,9 @@ public class StructuralSearchProfileActionProvider extends InspectionProfileActi
     return true;
   }
 
-  private static void addInspectionToProfile(@NotNull Project project, InspectionProfileImpl profile, Configuration configuration) {
+  private static void addInspectionToProfile(@NotNull Project project,
+                                             @NotNull InspectionProfileImpl profile,
+                                             @NotNull Configuration configuration) {
     final String shortName = configuration.getUuid().toString();
     final InspectionToolWrapper<?, ?> toolWrapper = profile.getInspectionTool(shortName, project);
     if (toolWrapper != null) {
@@ -187,7 +187,7 @@ public class StructuralSearchProfileActionProvider extends InspectionProfileActi
     private final EditorTextField myDescriptionTextArea;
     private final JTextField mySuppressIdTextField;
 
-    InspectionDataDialog(Project project, SSBasedInspection inspection, Configuration configuration, boolean newInspection) {
+    InspectionDataDialog(Project project, @NotNull SSBasedInspection inspection, @NotNull Configuration configuration, boolean newInspection) {
       super(null);
       myInspection = inspection;
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/StructuralSearchAction.java

@@ -22,7 +22,7 @@ public class StructuralSearchAction extends DumbAwareAction {
     triggerAction(null, new SearchContext(event.getDataContext()), false);
   }
 
-  public static void triggerAction(Configuration config, SearchContext searchContext, boolean replace) {
+  public static void triggerAction(Configuration config, @NotNull SearchContext searchContext, boolean replace) {
     final Project project = searchContext.getProject();
     PsiDocumentManager.getInstance(project).commitAllDocuments();
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/ReplaceOptions.java

@@ -22,6 +22,7 @@ public class ReplaceOptions implements JDOMExternalizable {
   private boolean toShortenFQN;
   private boolean myToReformatAccordingToStyle;
   private boolean myToUseStaticImport;
+  @NotNull
   private final MatchOptions matchOptions;
 
   @NonNls private static final String REFORMAT_ATTR_NAME = "reformatAccordingToStyle";
@@ -35,14 +36,14 @@ public class ReplaceOptions implements JDOMExternalizable {
     this(new MatchOptions());
   }
 
-  public ReplaceOptions(MatchOptions matchOptions) {
+  public ReplaceOptions(@NotNull MatchOptions matchOptions) {
     variableDefs = new LinkedHashMap<>();
     this.matchOptions = matchOptions;
     replacement = "";
     myToUseStaticImport = false;
   }
 
-  ReplaceOptions(ReplaceOptions options) {
+  private ReplaceOptions(@NotNull ReplaceOptions options) {
     variableDefs = new LinkedHashMap<>(options.variableDefs.size());
     options.variableDefs.forEach((key, value) -> variableDefs.put(key, value.copy())); // deep copy
     replacement = options.replacement;
@@ -52,10 +53,12 @@ public class ReplaceOptions implements JDOMExternalizable {
     matchOptions = options.matchOptions.copy(); // deep copy
   }
 
+  @NotNull
   public ReplaceOptions copy() {
     return new ReplaceOptions(this);
   }
 
+  @NotNull
   public String getReplacement() {
     return replacement;
   }
@@ -76,7 +79,7 @@ public class ReplaceOptions implements JDOMExternalizable {
     return myToReformatAccordingToStyle;
   }
 
-  public MatchOptions getMatchOptions() {
+  public @NotNull MatchOptions getMatchOptions() {
     return matchOptions;
   }
 
@@ -92,6 +95,7 @@ public class ReplaceOptions implements JDOMExternalizable {
     myToUseStaticImport = useStaticImport;
   }
 
+  @NotNull
   private Set<String> getUsedVariableNames() {
     return TemplateImplUtil.parseVariableNames(replacement);
   }
@@ -179,20 +183,22 @@ public class ReplaceOptions implements JDOMExternalizable {
     return result;
   }
 
-  public ReplacementVariableDefinition getVariableDefinition(String name) {
+  public ReplacementVariableDefinition getVariableDefinition(@NotNull String name) {
     return variableDefs != null ? variableDefs.get(name): null;
   }
 
-  public void addVariableDefinition(ReplacementVariableDefinition definition) {
+  public void addVariableDefinition(@NotNull ReplacementVariableDefinition definition) {
     variableDefs.put(definition.getName(), definition);
   }
 
-  public ReplacementVariableDefinition addNewVariableDefinition(String name) {
+  @NotNull
+  public ReplacementVariableDefinition addNewVariableDefinition(@NotNull String name) {
     final ReplacementVariableDefinition definition = new ReplacementVariableDefinition(name);
     variableDefs.put(name, definition);
     return definition;
   }
 
+  @NotNull
   public Collection<ReplacementVariableDefinition> getVariableDefinitions() {
     return variableDefs.values();
   }

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/ReplacementInfo.java

@@ -3,6 +3,7 @@ package com.intellij.structuralsearch.plugin.replace;
 
 import com.intellij.psi.PsiElement;
 import com.intellij.structuralsearch.MatchResult;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 public interface ReplacementInfo {
@@ -13,11 +14,12 @@ public interface ReplacementInfo {
 
   int getMatchesCount();
 
-  MatchResult getNamedMatchResult(String name);
+  MatchResult getNamedMatchResult(@NotNull String name);
 
+  @NotNull
   MatchResult getMatchResult();
 
-  String getVariableName(PsiElement element);
+  String getVariableName(@NotNull PsiElement element);
 
-  String getSearchPatternName(String sourceName);
+  String getSearchPatternName(@NotNull String sourceName);
 }

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/impl/ParameterInfo.java

@@ -3,8 +3,10 @@ package com.intellij.structuralsearch.plugin.replace.impl;
 
 import com.intellij.openapi.util.UserDataHolderBase;
 import com.intellij.psi.PsiElement;
+import org.jetbrains.annotations.NotNull;
 
 public final class ParameterInfo extends UserDataHolderBase {
+  @NotNull
   private final String name;
   private final int startIndex;
   private final boolean replacementVariable;
@@ -16,13 +18,13 @@ public final class ParameterInfo extends UserDataHolderBase {
   private boolean hasCommaAfter;
   private PsiElement myElement;
 
-  public ParameterInfo(String name, int startIndex, boolean replacementVariable) {
+  public ParameterInfo(@NotNull String name, int startIndex, boolean replacementVariable) {
     this.name = name;
     this.startIndex = startIndex;
     this.replacementVariable = replacementVariable;
   }
 
-  public String getName() {
+  public @NotNull String getName() {
     return name;
   }
 
@@ -86,7 +88,7 @@ public final class ParameterInfo extends UserDataHolderBase {
     return myElement;
   }
 
-  public void setElement(PsiElement element) {
+  public void setElement(@NotNull PsiElement element) {
     myElement = element;
   }
 }

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/impl/ReplacementBuilder.java

@@ -27,13 +27,14 @@ import java.util.*;
  * @author maxim
  */
 public final class ReplacementBuilder {
+  @NotNull
   private final String replacement;
   private final MultiMap<String, ParameterInfo> parameterizations = MultiMap.createLinked();
   private final Map<String, ScriptSupport> replacementVarsMap = new HashMap<>();
   private final ReplaceOptions options;
   private final Project myProject;
 
-  ReplacementBuilder(Project project, ReplaceOptions options) {
+  ReplacementBuilder(@NotNull Project project, @NotNull ReplaceOptions options) {
     myProject = project;
     this.options = options;
 
@@ -121,7 +122,8 @@ public final class ReplacementBuilder {
     }
   }
 
-  String process(MatchResult match, ReplacementInfo replacementInfo, LanguageFileType type) {
+  @NotNull
+  String process(@NotNull MatchResult match, @NotNull ReplacementInfo replacementInfo, @NotNull LanguageFileType type) {
     if (parameterizations.isEmpty()) {
       return replacement;
     }
@@ -156,7 +158,7 @@ public final class ReplacementBuilder {
   }
 
   @Nullable
-  private Object generateReplacement(ParameterInfo info, MatchResult match) {
+  private Object generateReplacement(@NotNull ParameterInfo info, @NotNull MatchResult match) {
     ScriptSupport scriptSupport = replacementVarsMap.get(info.getName());
 
     if (scriptSupport == null) {

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/impl/ReplacementInfoImpl.java

@@ -10,6 +10,7 @@ import com.intellij.structuralsearch.MatchResult;
 import com.intellij.structuralsearch.StructuralSearchUtil;
 import com.intellij.structuralsearch.plugin.replace.ReplacementInfo;
 import com.intellij.util.SmartList;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.HashMap;
@@ -18,6 +19,7 @@ import java.util.List;
 import java.util.Map;
 
 class ReplacementInfoImpl implements ReplacementInfo {
+  @NotNull
   private final MatchResult matchResult;
   private final List<SmartPsiElementPointer<PsiElement>> matchesPtrList = new SmartList<>();
   private final Map<String, MatchResult> variableMap = new HashMap<>();
@@ -26,12 +28,12 @@ class ReplacementInfoImpl implements ReplacementInfo {
 
   private String replacement;
 
-  ReplacementInfoImpl(MatchResult matchResult, Project project) {
+  ReplacementInfoImpl(@NotNull MatchResult matchResult, @NotNull Project project) {
     this.matchResult = matchResult;
     init(project);
   }
 
-  private void init(Project project) {
+  private void init(@NotNull Project project) {
     fillPointerList(project);
     fillVariableMap(matchResult.getRoot());
     for(Map.Entry<String, MatchResult> entry : variableMap.entrySet()) {
@@ -44,7 +46,7 @@ class ReplacementInfoImpl implements ReplacementInfo {
     return replacement;
   }
 
-  public void setReplacement(String replacement) {
+  public void setReplacement(@NotNull String replacement) {
     this.replacement = replacement;
   }
 
@@ -60,26 +62,26 @@ class ReplacementInfoImpl implements ReplacementInfo {
   }
 
   @Override
-  public MatchResult getNamedMatchResult(String name) {
+  public MatchResult getNamedMatchResult(@NotNull String name) {
     return variableMap.get(name);
   }
 
   @Override
-  public MatchResult getMatchResult() {
+  public @NotNull MatchResult getMatchResult() {
     return matchResult;
   }
 
   @Override
-  public String getVariableName(PsiElement element) {
+  public String getVariableName(@NotNull PsiElement element) {
     return elementToVariableNameMap.get(element);
   }
 
   @Override
-  public String getSearchPatternName(String sourceName) {
+  public String getSearchPatternName(@NotNull String sourceName) {
     return sourceNameToSearchPatternNameMap.get(sourceName);
   }
 
-  private void fillPointerList(Project project) {
+  private void fillPointerList(@NotNull Project project) {
     final SmartPointerManager manager = SmartPointerManager.getInstance(project);
 
     if (MatchResult.MULTI_LINE_MATCH.equals(matchResult.getName())) {

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/impl/Replacer.java

@@ -26,6 +26,7 @@ import com.intellij.structuralsearch.plugin.replace.ReplacementInfo;
 import com.intellij.structuralsearch.plugin.util.CollectingMatchResultSink;
 import com.intellij.util.IncorrectOperationException;
 import com.intellij.util.SmartList;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
@@ -35,12 +36,13 @@ import java.util.List;
  */
 public class Replacer {
   private final Project project;
+  @NotNull
   private final ReplaceOptions options;
   private final StructuralReplaceHandler replaceHandler;
   private final ReplacementBuilder replacementBuilder;
-  private PsiElement lastAffectedElement = null;
+  private PsiElement lastAffectedElement;
 
-  public Replacer(Project project, ReplaceOptions options) {
+  public Replacer(@NotNull Project project, @NotNull ReplaceOptions options) {
     this.project = project;
     this.options = options;
     final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByFileType(options.getMatchOptions().getFileType());
@@ -68,11 +70,11 @@ public class Replacer {
 
   public static String testReplace(String in, String what, String by, ReplaceOptions options, Project project, boolean sourceIsFile) {
     final LanguageFileType type = options.getMatchOptions().getFileType();
-    return testReplace(in, what, by, options, project, sourceIsFile, false, type, null);
+    return testReplace(in, what, by, options, project, sourceIsFile, false, type, type.getLanguage());
   }
 
   public static String testReplace(String in, String what, String by, ReplaceOptions replaceOptions, Project project, boolean sourceIsFile,
-                                   boolean createPhysicalFile, LanguageFileType sourceFileType, Language sourceDialect) {
+                                   boolean createPhysicalFile, @NotNull LanguageFileType sourceFileType, @NotNull Language sourceDialect) {
     replaceOptions.setReplacement(by);
 
     final MatchOptions matchOptions = replaceOptions.getMatchOptions();
@@ -84,12 +86,15 @@ public class Replacer {
     final Replacer replacer = new Replacer(project, replaceOptions);
     final Matcher matcher = new Matcher(project, matchOptions);
     try {
-      final PsiElement firstElement, lastElement, parent;
+      final PsiElement firstElement;
+      final PsiElement lastElement;
+      final PsiElement parent;
       if (matchOptions.getScope() == null) {
         final PsiElement[] elements = MatcherImplUtil.createTreeFromText(
           in,
           new PatternContextInfo(sourceIsFile ? PatternTreeContext.File : PatternTreeContext.Block),
-          sourceFileType, sourceDialect,
+          sourceFileType,
+          sourceDialect,
           project,
           createPhysicalFile
         );
@@ -188,13 +193,13 @@ public class Replacer {
     );
   }
 
-  public void replace(ReplacementInfo info) {
+  public void replace(@NotNull ReplacementInfo info) {
     replaceHandler.prepare(info);
     reformatAndPostProcess(doReplace(info));
   }
 
   @Nullable
-  private PsiElement doReplace(ReplacementInfo info) {
+  private PsiElement doReplace(@NotNull ReplacementInfo info) {
     final PsiElement element = info.getMatch(0);
 
     if (element==null || !element.isWritable() || !element.isValid()) return null;
@@ -258,7 +263,7 @@ public class Replacer {
     }
   }
 
-  public static void checkReplacementPattern(Project project, ReplaceOptions options) {
+  public static void checkReplacementPattern(@NotNull Project project, @NotNull ReplaceOptions options) {
     try {
       final String search = options.getMatchOptions().getSearchPattern();
       final String replacement = options.getReplacement();
@@ -309,7 +314,8 @@ public class Replacer {
     }
   }
 
-  public ReplacementInfo buildReplacement(MatchResult result) {
+  @NotNull
+  public ReplacementInfo buildReplacement(@NotNull MatchResult result) {
     final ReplacementInfoImpl replacementInfo = new ReplacementInfoImpl(result, project);
     replacementInfo.setReplacement(replacementBuilder.process(result, replacementInfo, options.getMatchOptions().getFileType()));
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/impl/ReplacerUtil.java

@@ -6,6 +6,7 @@ import com.intellij.psi.PsiComment;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiWhiteSpace;
 import com.intellij.structuralsearch.StructuralSearchProfile;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Eugene.Kudelevsky
@@ -14,10 +15,10 @@ public final class ReplacerUtil {
   private ReplacerUtil() {
   }
 
-  public static PsiElement copySpacesAndCommentsBefore(PsiElement elementToReplace,
-                                                       PsiElement[] patternElements,
-                                                       String replacementToMake,
-                                                       PsiElement elementParent) {
+  public static PsiElement copySpacesAndCommentsBefore(@NotNull PsiElement elementToReplace,
+                                                       PsiElement @NotNull [] patternElements,
+                                                       @NotNull String replacementToMake,
+                                                       @NotNull PsiElement elementParent) {
     int i = 0;
     while (true) {    // if it goes out of bounds then deep error happens
       if (!(patternElements[i] instanceof PsiComment || patternElements[i] instanceof PsiWhiteSpace)) {

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/ui/ReplaceCommand.java

@@ -7,17 +7,18 @@ import com.intellij.structuralsearch.plugin.ui.SearchCommand;
 import com.intellij.structuralsearch.plugin.ui.SearchContext;
 import com.intellij.structuralsearch.plugin.ui.UsageViewContext;
 import com.intellij.usages.Usage;
+import org.jetbrains.annotations.NotNull;
 
 public class ReplaceCommand extends SearchCommand {
 
   private ReplaceUsageViewContext myReplaceUsageViewContext;
 
-  public ReplaceCommand(Configuration configuration, SearchContext searchContext) {
+  public ReplaceCommand(@NotNull Configuration configuration, @NotNull SearchContext searchContext) {
     super(configuration, searchContext);
   }
 
   @Override
-  protected UsageViewContext createUsageViewContext() {
+  protected @NotNull UsageViewContext createUsageViewContext() {
     final Runnable searchStarter = () -> new ReplaceCommand(myConfiguration, mySearchContext).startSearching();
     myReplaceUsageViewContext = new ReplaceUsageViewContext(mySearchContext, myConfiguration, searchStarter);
     return myReplaceUsageViewContext;

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/ui/ReplaceConfiguration.java

@@ -7,12 +7,13 @@ import com.intellij.structuralsearch.plugin.replace.ReplaceOptions;
 import com.intellij.structuralsearch.plugin.ui.Configuration;
 import com.intellij.util.ObjectUtils;
 import org.jdom.Element;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author Maxim.Mossienko
  */
 public class ReplaceConfiguration extends Configuration {
-
+  @NotNull
   private final ReplaceOptions myReplaceOptions;
   public static final String REPLACEMENT_VARIABLE_SUFFIX = "$replacement";
 
@@ -20,35 +21,35 @@ public class ReplaceConfiguration extends Configuration {
     myReplaceOptions = new ReplaceOptions();
   }
 
-  public ReplaceConfiguration(Configuration configuration) {
+  public ReplaceConfiguration(@NotNull Configuration configuration) {
     super(configuration);
     myReplaceOptions = configuration instanceof ReplaceConfiguration
                        ? ((ReplaceConfiguration)configuration).myReplaceOptions.copy()
                        : new ReplaceOptions(configuration.getMatchOptions().copy());
   }
 
-  public ReplaceConfiguration(String name, String category) {
+  public ReplaceConfiguration(@NotNull String name, @NotNull String category) {
     super(name, category);
     myReplaceOptions = new ReplaceOptions();
   }
 
   @Override
-  public ReplaceConfiguration copy() {
+  public @NotNull ReplaceConfiguration copy() {
     return new ReplaceConfiguration(this);
   }
 
   @Override
-  public ReplaceOptions getReplaceOptions() {
+  public @NotNull ReplaceOptions getReplaceOptions() {
     return myReplaceOptions;
   }
 
   @Override
-  public MatchOptions getMatchOptions() {
+  public @NotNull MatchOptions getMatchOptions() {
     return myReplaceOptions.getMatchOptions();
   }
 
   @Override
-  public NamedScriptableDefinition findVariable(String name) {
+  public NamedScriptableDefinition findVariable(@NotNull String name) {
     return ObjectUtils.chooseNotNull(myReplaceOptions.getVariableDefinition(name), getMatchOptions().getVariableConstraint(name));
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/replace/ui/ReplaceUsageViewContext.java

@@ -25,18 +25,18 @@ import java.util.*;
 import java.util.stream.Collectors;
 
 class ReplaceUsageViewContext extends UsageViewContext {
-  private final HashMap<Usage,ReplacementInfo> usage2ReplacementInfo = new HashMap<>();
+  private final Map<Usage,ReplacementInfo> usage2ReplacementInfo = new HashMap<>();
   private final Replacer replacer = new Replacer(mySearchContext.getProject(), myConfiguration.getReplaceOptions());
 
-  ReplaceUsageViewContext(SearchContext context, Configuration configuration, Runnable searchStarter) {
+  ReplaceUsageViewContext(@NotNull SearchContext context, @NotNull Configuration configuration, @NotNull Runnable searchStarter) {
     super(configuration, context, searchStarter);
   }
 
-  public void addReplaceUsage(Usage usage, MatchResult result) {
+  public void addReplaceUsage(@NotNull Usage usage, @NotNull MatchResult result) {
     usage2ReplacementInfo.put(usage, replacer.buildReplacement(result));
   }
 
-  private static boolean isValid(UsageInfo2UsageAdapter info) {
+  private static boolean isValid(@NotNull UsageInfo2UsageAdapter info) {
     final PsiElement element = info.getUsageInfo().getElement();
     return element != null && element.isValid();
   }
@@ -69,7 +69,7 @@ class ReplaceUsageViewContext extends UsageViewContext {
     myUsageView.addButtonToLowerPane(previewReplacement, SSRBundle.message("preview.replacement.button"));
   }
 
-  private void replace(@NotNull Collection<Usage> usages) {
+  private void replace(@NotNull Collection<? extends Usage> usages) {
     final Set<Usage> excluded = myUsageView.getExcludedUsages();
     usages = usages.stream().filter(u -> !excluded.contains(u)).filter(u -> isValid((UsageInfo2UsageAdapter)u)).collect(Collectors.toList());
 
@@ -88,7 +88,7 @@ class ReplaceUsageViewContext extends UsageViewContext {
     }
   }
 
-  private void removeUsagesAndSelectNext(Collection<Usage> usages, Collection<Usage> excluded) {
+  private void removeUsagesAndSelectNext(@NotNull Collection<? extends Usage> usages, @NotNull Collection<? extends Usage> excluded) {
     final List<Usage> sortedUsages = myUsageView.getSortedUsages();
     if (sortedUsages.size() == usages.size()) {
       myUsageView.close();

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/Configuration.java

@@ -40,7 +40,7 @@ public abstract class Configuration implements JDOMExternalizable, Comparable<Co
   private String problemDescriptor;
   private int order;
 
-  private transient String myCurrentVariableName = null;
+  private transient String myCurrentVariableName;
 
   public Configuration() {
     name = "";
@@ -48,13 +48,13 @@ public abstract class Configuration implements JDOMExternalizable, Comparable<Co
     created = -1L;
   }
 
-  public Configuration(String name, String category) {
+  public Configuration(@NotNull String name, @NotNull String category) {
     this.name = name;
     this.category = category;
     created = -1L;
   }
 
-  protected Configuration(Configuration configuration) {
+  protected Configuration(@NotNull Configuration configuration) {
     name = configuration.name;
     category = configuration.category;
     created = -1L; // receives timestamp when added to history
@@ -66,6 +66,7 @@ public abstract class Configuration implements JDOMExternalizable, Comparable<Co
     order = configuration.order;
   }
 
+  @NotNull
   public abstract Configuration copy();
 
   @NotNull
@@ -80,6 +81,7 @@ public abstract class Configuration implements JDOMExternalizable, Comparable<Co
     name = value;
   }
 
+  @NotNull
   public String getCategory() {
     return category;
   }
@@ -210,13 +212,13 @@ public abstract class Configuration implements JDOMExternalizable, Comparable<Co
     this.predefined = predefined;
   }
 
+  @NotNull
   public abstract MatchOptions getMatchOptions();
 
-  public ReplaceOptions getReplaceOptions() {
-    return null;
-  }
+  @NotNull
+  public abstract ReplaceOptions getReplaceOptions();
 
-  public abstract NamedScriptableDefinition findVariable(String name);
+  public abstract NamedScriptableDefinition findVariable(@NotNull String name);
 
   public abstract void removeUnusedVariables();
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/ConfigurationManager.java

@@ -25,8 +25,8 @@ import java.util.stream.Stream;
 @State(name = "StructuralSearchPlugin", storages = @Storage(StoragePathMacros.WORKSPACE_FILE))
 public class ConfigurationManager implements PersistentStateComponent<Element> {
   private static final int MAX_RECENT_SIZE = 30;
-  @NonNls static final String SEARCH_TAG_NAME = "searchConfiguration";
-  @NonNls static final String REPLACE_TAG_NAME = "replaceConfiguration";
+  @NonNls private static final String SEARCH_TAG_NAME = "searchConfiguration";
+  @NonNls private static final String REPLACE_TAG_NAME = "replaceConfiguration";
   @NonNls private static final String SAVE_HISTORY_ATTR_NAME = "history";
 
   private final List<Configuration> configurations = new SmartList<>();
@@ -65,9 +65,8 @@ public class ConfigurationManager implements PersistentStateComponent<Element> {
   }
   /**
    * Stores configurations at the application level. Before the configurations where stored in the workspace file.
-   * @param configurations
    */
-  private void migrate(List<? extends Configuration> configurations) {
+  private void migrate(@NotNull List<? extends Configuration> configurations) {
     if (configurations.isEmpty()) {
       return;
     }
@@ -132,7 +131,8 @@ public class ConfigurationManager implements PersistentStateComponent<Element> {
     }
   }
 
-  static Element saveConfiguration(@NotNull Element element, @NotNull Configuration config) {
+  @NotNull
+  private static Element saveConfiguration(@NotNull Element element, @NotNull Configuration config) {
     final Element infoElement = new Element(config instanceof SearchConfiguration ? SEARCH_TAG_NAME : REPLACE_TAG_NAME);
     element.addContent(infoElement);
     config.writeExternal(infoElement);
@@ -159,7 +159,7 @@ public class ConfigurationManager implements PersistentStateComponent<Element> {
     }
   }
 
-  static Configuration readConfiguration(@NotNull Element element) {
+  private static Configuration readConfiguration(@NotNull Element element) {
     final String name = element.getName();
     final Configuration config;
     if (name.equals(SEARCH_TAG_NAME)) {

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/SearchCommand.java

@@ -19,16 +19,18 @@ import com.intellij.util.Processor;
 import org.jetbrains.annotations.NotNull;
 
 public class SearchCommand {
+  @NotNull
   protected final SearchContext mySearchContext;
+  @NotNull
   protected final Configuration myConfiguration;
-  private MatchingProcess process;
   private FindUsagesProcessPresentation myProcessPresentation;
 
-  public SearchCommand(Configuration configuration, SearchContext searchContext) {
+  public SearchCommand(@NotNull Configuration configuration, @NotNull SearchContext searchContext) {
     myConfiguration = configuration;
     mySearchContext = searchContext;
   }
 
+  @NotNull
   protected UsageViewContext createUsageViewContext() {
     final Runnable searchStarter = () -> new SearchCommand(myConfiguration, mySearchContext).startSearching();
     return new UsageViewContext(myConfiguration, mySearchContext, searchStarter);
@@ -49,12 +51,7 @@ public class SearchCommand {
     ((FindManagerImpl)FindManager.getInstance(mySearchContext.getProject())).getFindUsagesManager().addToHistory(target);
     UsageViewManager.getInstance(mySearchContext.getProject()).searchAndShowUsages(
       new UsageTarget[]{target},
-      () -> new UsageSearcher() {
-        @Override
-        public void generate(@NotNull final Processor<? super Usage> processor) {
-          findUsages(processor);
-        }
-      },
+      () -> processor -> findUsages(processor),
       myProcessPresentation,
       presentation,
       new UsageViewManager.UsageViewStateListener() {
@@ -70,7 +67,7 @@ public class SearchCommand {
     );
   }
 
-  public void findUsages(final Processor<? super Usage> processor) {
+  public void findUsages(@NotNull Processor<? super Usage> processor) {
     final ProgressIndicator progress = ProgressManager.getInstance().getProgressIndicator();
     progress.setIndeterminate(false);
 
@@ -78,13 +75,12 @@ public class SearchCommand {
       int count;
 
       @Override
-      public void setMatchingProcess(MatchingProcess _process) {
-        process = _process;
+      public void setMatchingProcess(@NotNull MatchingProcess _process) {
         findStarted();
       }
 
       @Override
-      public void processFile(PsiFile element) {
+      public void processFile(@NotNull PsiFile element) {
         final VirtualFile virtualFile = element.getVirtualFile();
         if (virtualFile != null)
           progress.setText(SSRBundle.message("looking.in.progress.message", virtualFile.getPresentableName()));
@@ -103,7 +99,7 @@ public class SearchCommand {
       }
 
       @Override
-      public void newMatch(MatchResult result) {
+      public void newMatch(@NotNull MatchResult result) {
         UsageInfo info;
 
         if (MatchResult.MULTI_LINE_MATCH.equals(result.getName())) {

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/SearchConfiguration.java

@@ -3,7 +3,9 @@ package com.intellij.structuralsearch.plugin.ui;
 
 import com.intellij.structuralsearch.MatchOptions;
 import com.intellij.structuralsearch.NamedScriptableDefinition;
+import com.intellij.structuralsearch.plugin.replace.ReplaceOptions;
 import org.jdom.Element;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Configuration of the search
@@ -16,28 +18,33 @@ public class SearchConfiguration extends Configuration {
     matchOptions = new MatchOptions();
   }
 
-  SearchConfiguration(Configuration configuration) {
+  SearchConfiguration(@NotNull Configuration configuration) {
     super(configuration);
     matchOptions = configuration.getMatchOptions().copy();
   }
 
-  public SearchConfiguration(String name, String category) {
+  public SearchConfiguration(@NotNull String name, @NotNull String category) {
     super(name, category);
     matchOptions = new MatchOptions();
   }
 
   @Override
-  public SearchConfiguration copy() {
+  public @NotNull ReplaceOptions getReplaceOptions() {
+    throw new IllegalStateException();
+  }
+
+  @Override
+  public @NotNull SearchConfiguration copy() {
     return new SearchConfiguration(this);
   }
 
   @Override
-  public MatchOptions getMatchOptions() {
+  public @NotNull MatchOptions getMatchOptions() {
     return matchOptions;
   }
 
   @Override
-  public NamedScriptableDefinition findVariable(String name) {
+  public NamedScriptableDefinition findVariable(@NotNull String name) {
     return matchOptions.getVariableConstraint(name);
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/StructuralSearchDialog.java

@@ -73,15 +73,16 @@ import com.intellij.structuralsearch.plugin.replace.ui.ReplaceCommand;
 import com.intellij.structuralsearch.plugin.replace.ui.ReplaceConfiguration;
 import com.intellij.structuralsearch.plugin.ui.filters.FilterPanel;
 import com.intellij.structuralsearch.plugin.util.CollectingMatchResultSink;
-import com.intellij.ui.*;
+import com.intellij.ui.ComponentUtil;
+import com.intellij.ui.EditorTextField;
+import com.intellij.ui.IdeBorderFactory;
+import com.intellij.ui.OnePixelSplitter;
 import com.intellij.ui.awt.RelativePoint;
 import com.intellij.util.Alarm;
-import com.intellij.util.IconUtil;
 import com.intellij.util.SmartList;
 import com.intellij.util.concurrency.AppExecutorUtil;
 import com.intellij.util.messages.MessageBusConnection;
 import com.intellij.util.textCompletion.TextCompletionUtil;
-import com.intellij.util.ui.JBRectangle;
 import com.intellij.util.ui.TextTransferable;
 import org.jdom.JDOMException;
 import org.jetbrains.annotations.Nls;
@@ -93,8 +94,10 @@ import javax.swing.*;
 import javax.swing.border.Border;
 import java.awt.*;
 import java.awt.datatransfer.DataFlavor;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
-import java.util.*;
+import java.util.Objects;
 
 import static com.intellij.openapi.util.text.StringUtil.isEmpty;
 import static com.intellij.openapi.util.text.StringUtil.trimEnd;
@@ -122,18 +125,19 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
   private static final Key<Configuration> STRUCTURAL_SEARCH_PREVIOUS_CONFIGURATION = Key.create("STRUCTURAL_SEARCH_PREVIOUS_CONFIGURATION");
   public static final Key<Boolean> TEST_STRUCTURAL_SEARCH_DIALOG = Key.create("TEST_STRUCTURAL_SEARCH_DIALOG");
 
+  @NotNull
   private final SearchContext mySearchContext;
-  Editor myEditor;
-  boolean myReplace;
-  Configuration myConfiguration;
-  @NonNls LanguageFileType myFileType = StructuralSearchUtil.getDefaultFileType();
-  Language myDialect = null;
-  PatternContext myPatternContext = null;
-  final List<RangeHighlighter> myRangeHighlighters = new SmartList<>();
+  private Editor myEditor;
+  private boolean myReplace;
+  @NotNull
+  private Configuration myConfiguration;
+  @NotNull
+  @NonNls private LanguageFileType myFileType = StructuralSearchUtil.getDefaultFileType();
+  private Language myDialect;
+  private PatternContext myPatternContext;
+  private final List<RangeHighlighter> myRangeHighlighters = new SmartList<>();
   private final DocumentListener myRestartHighlightingListener = new DocumentListener() {
-    final Runnable runnable = () -> ReadAction.nonBlocking(() -> {
-      addMatchHighlights();
-    })
+    final Runnable runnable = () -> ReadAction.nonBlocking(() -> addMatchHighlights())
       .withDocumentsCommitted(getProject())
       .expireWith(getDisposable())
       .coalesceBy(this)
@@ -155,20 +159,20 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
   private boolean myFilterIsShowing;
 
   // components
-  final FileTypeChooser myFileTypeChooser = new FileTypeChooser();
-  ActionToolbarImpl myOptionsToolbar;
-  EditorTextField mySearchCriteriaEdit;
-  EditorTextField myReplaceCriteriaEdit;
-  OnePixelSplitter mySearchEditorPanel;
+  private final FileTypeChooser myFileTypeChooser = new FileTypeChooser();
+  private ActionToolbarImpl myOptionsToolbar;
+  private EditorTextField mySearchCriteriaEdit;
+  private EditorTextField myReplaceCriteriaEdit;
+  private OnePixelSplitter mySearchEditorPanel;
 
-  FilterPanel myFilterPanel;
+  private FilterPanel myFilterPanel;
   private LinkComboBox myTargetComboBox;
   private ScopePanel myScopePanel;
   private JCheckBox myOpenInNewTab;
 
-  JComponent myReplacePanel;
+  private JComponent myReplacePanel;
 
-  public StructuralSearchDialog(SearchContext searchContext, boolean replace) {
+  public StructuralSearchDialog(@NotNull SearchContext searchContext, boolean replace) {
     this(searchContext, replace, false);
   }
 
@@ -264,7 +268,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     initiateValidation();
   }
 
-  void initiateValidation() {
+  private void initiateValidation() {
     if (myAlarm.isDisposed()) return;
     myAlarm.cancelAllRequests();
     myAlarm.addRequest(() -> {
@@ -313,13 +317,12 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     }, ModalityState.stateForComponent(myFilterPanel.getComponent()));
   }
 
+  @NotNull
   private Configuration createConfiguration(Configuration template) {
     if (myReplace) {
       return (template == null) ? new ReplaceConfiguration(getUserDefined(), getUserDefined()) : new ReplaceConfiguration(template);
     }
-    else {
-      return (template == null) ? new SearchConfiguration(getUserDefined(), getUserDefined()) : new SearchConfiguration(template);
-    }
+    return (template == null) ? new SearchConfiguration(getUserDefined(), getUserDefined()) : new SearchConfiguration(template);
   }
 
   private void setTextFromContext() {
@@ -345,7 +348,8 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     final Configuration previousConfiguration = getProject().getUserData(STRUCTURAL_SEARCH_PREVIOUS_CONFIGURATION);
     if (previousConfiguration != null) {
       loadConfiguration(previousConfiguration);
-    } else {
+    }
+    else {
       final Configuration configuration = ConfigurationManager.getInstance(getProject()).getMostRecentConfiguration();
       if (configuration != null) {
         loadConfiguration(configuration);
@@ -380,7 +384,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
   @NotNull
   @Nls
   @NlsContexts.DialogTitle
-  String getDefaultTitle() {
+  private String getDefaultTitle() {
     return myReplace ? SSRBundle.message("structural.replace.title") : SSRBundle.message("structural.search.title");
   }
 
@@ -752,7 +756,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     return panel;
   }
 
-  Project getProject() {
+  private Project getProject() {
     return mySearchContext.getProject();
   }
 
@@ -898,7 +902,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     }
   }
 
-  void removeMatchHighlights() {
+  private void removeMatchHighlights() {
     if (myEditConfigOnly) {
       return;
     }
@@ -921,7 +925,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     });
   }
 
-  void addMatchHighlights() {
+  private void addMatchHighlights() {
     if (myEditConfigOnly) {
       return;
     }
@@ -950,7 +954,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     }
   }
 
-  private void addMatchHighlights(@NotNull List<MatchResult> matchResults,
+  private void addMatchHighlights(@NotNull List<? extends MatchResult> matchResults,
                                   @NotNull Editor editor,
                                   @NotNull PsiFile file,
                                   @Nullable String statusBarText) {
@@ -992,8 +996,8 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     });
   }
 
-  Balloon myBalloon = null;
-  void reportMessage(@Nullable String message, boolean error, @NotNull JComponent component) {
+  private Balloon myBalloon;
+  private void reportMessage(@Nullable String message, boolean error, @NotNull JComponent component) {
     ApplicationManager.getApplication().invokeLater(() -> {
       if (myBalloon != null) myBalloon.hide();
       component.putClientProperty("JComponent.outline", (!error || message == null) ? null : "error");
@@ -1015,7 +1019,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     }, ModalityState.stateForComponent(component));
   }
 
-  void securityCheck() {
+  private void securityCheck() {
     final MatchOptions matchOptions = myConfiguration.getMatchOptions();
     int scripts = 0;
     for (String name : matchOptions.getVariableConstraintNames()) {
@@ -1023,10 +1027,8 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
       if (constraint.getScriptCodeConstraint().length() > 2) scripts++;
     }
     final ReplaceOptions replaceOptions = myConfiguration.getReplaceOptions();
-    if (replaceOptions != null) {
-      for (ReplacementVariableDefinition variableDefinition : replaceOptions.getVariableDefinitions()) {
-        if (variableDefinition.getScriptCodeConstraint().length() > 2) scripts++;
-      }
+    for (ReplacementVariableDefinition variableDefinition : replaceOptions.getVariableDefinitions()) {
+      if (variableDefinition.getScriptCodeConstraint().length() > 2) scripts++;
     }
     if (scripts > 0) {
       UIUtil.SSR_NOTIFICATION_GROUP.createNotification(NotificationType.WARNING)
@@ -1042,7 +1044,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     myConfiguration.setCurrentVariableName(variableName);
   }
 
-  void setFilterPanelVisible(boolean visible) {
+  private void setFilterPanelVisible(boolean visible) {
     if (visible) {
       if (myFilterPanel.getVariable() == null) {
         myFilterPanel.initFilters(UIUtil.getOrAddVariableConstraint(Configuration.CONTEXT_VAR_NAME, myConfiguration));
@@ -1059,7 +1061,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     }
   }
 
-  boolean isFilterPanelVisible() {
+  private boolean isFilterPanelVisible() {
     return mySearchEditorPanel.getSecondComponent() != null;
   }
 
@@ -1089,7 +1091,7 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
    * @param text  the text to try and load a configuration from
    * @return {@code true}, if some configuration was found, even if it was broken or corrupted {@code false} otherwise.
    */
-  boolean loadConfiguration(String text) {
+  private boolean loadConfiguration(String text) {
     if (text == null) {
       return false;
     }
@@ -1172,15 +1174,12 @@ public class StructuralSearchDialog extends DialogWrapper implements DocumentLis
     matchOptions.setPatternContext(myPatternContext);
     matchOptions.setSearchPattern(getPattern(mySearchCriteriaEdit));
 
-    final ReplaceOptions replaceOptions = myConfiguration.getReplaceOptions();
-
-    if (myReplace) {
-      replaceOptions.setReplacement(getPattern(myReplaceCriteriaEdit));
-      matchOptions.setRecursiveSearch(false);
-    }
 
     final PropertiesComponent properties = PropertiesComponent.getInstance();
     if (myReplace) {
+      final ReplaceOptions replaceOptions = myConfiguration.getReplaceOptions();
+      replaceOptions.setReplacement(getPattern(myReplaceCriteriaEdit));
+      matchOptions.setRecursiveSearch(false);
       properties.setValue(SHORTEN_FQN_STATE, replaceOptions.isToShortenFQN());
       properties.setValue(USE_STATIC_IMPORT_STATE, replaceOptions.isToUseStaticImport());
       properties.setValue(REFORMAT_STATE, replaceOptions.isToReformatAccordingToStyle());

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/StructuralSearchTemplatesCompletionContributor.java

@@ -15,7 +15,7 @@ import com.intellij.structuralsearch.MatchOptions;
 import com.intellij.ui.TextFieldWithAutoCompletionListProvider;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.LinkedHashSet;
+import java.util.Set;
 
 public class StructuralSearchTemplatesCompletionContributor extends CompletionContributor {
   @Override
@@ -34,7 +34,7 @@ public class StructuralSearchTemplatesCompletionContributor extends CompletionCo
     final CharSequence text = document.getCharsSequence();
     if (StringUtil.startsWithChar(shortPrefix, '$')) {
       shortPrefix = shortPrefix.substring(1);
-      final LinkedHashSet<String> variableNames = TemplateImplUtil.parseVariableNames(text);
+      Set<String> variableNames = TemplateImplUtil.parseVariableNames(text);
       for (String name : variableNames) {
         if (name.startsWith(shortPrefix) && !name.equals(shortPrefix)) {
           result.addElement(LookupElementBuilder.create('$' + name + '$')
@@ -75,7 +75,7 @@ public class StructuralSearchTemplatesCompletionContributor extends CompletionCo
           .withPresentableText(configurationName);
         if (dialog != null)
           element = element.withInsertHandler((InsertionContext context, LookupElement item) -> context.setLaterRunnable(
-            () -> { dialog.loadConfiguration((Configuration)item.getObject()); }
+            () -> dialog.loadConfiguration((Configuration)item.getObject())
           ));
         insensitive.addElement(element);
       }

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/StructuralSearchUsageTarget.java

@@ -23,7 +23,7 @@ class StructuralSearchUsageTarget implements ConfigurableUsageTarget, ItemPresen
   private final Runnable mySearchStarter;
   private final SearchContext mySearchContext;
 
-  StructuralSearchUsageTarget(Configuration configuration, SearchContext searchContext, Runnable searchStarter) {
+  StructuralSearchUsageTarget(@NotNull Configuration configuration, @NotNull SearchContext searchContext, @NotNull Runnable searchStarter) {
     myConfiguration = configuration;
     mySearchStarter = searchStarter;
     mySearchContext = searchContext;

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/UIUtil.java

@@ -114,18 +114,18 @@ public final class UIUtil {
                                              () -> document.replaceString(0, document.getTextLength(), value));
   }
 
-  public static void setContent(@NotNull EditorTextField editor, String text) {
-    final String value = text != null ? text : "";
+  public static void setContent(@NotNull EditorTextField editor, @NotNull String text) {
     final Document document = editor.getDocument();
     WriteCommandAction.runWriteCommandAction(editor.getProject(), SSRBundle.message("modify.editor.content.command.name"), SS_GROUP,
-                                             () -> document.replaceString(0, document.getTextLength(), value));
+                                             () -> document.replaceString(0, document.getTextLength(), text));
   }
 
-  public static void invokeAction(Configuration config, SearchContext context) {
+  public static void invokeAction(@NotNull Configuration config, @NotNull SearchContext context) {
     StructuralSearchAction.triggerAction(config, context, !(config instanceof SearchConfiguration));
   }
 
-  public static MatchVariableConstraint getOrAddVariableConstraint(String varName, Configuration configuration) {
+  @NotNull
+  public static MatchVariableConstraint getOrAddVariableConstraint(@NotNull String varName, @NotNull Configuration configuration) {
     final MatchOptions options = configuration.getMatchOptions();
     final MatchVariableConstraint varInfo = options.getVariableConstraint(varName);
 
@@ -135,7 +135,8 @@ public final class UIUtil {
     return configuration.getMatchOptions().addNewVariableConstraint(varName);
   }
 
-  public static ReplacementVariableDefinition getOrAddReplacementVariable(String varName, Configuration configuration) {
+  @NotNull
+  public static ReplacementVariableDefinition getOrAddReplacementVariable(@NotNull String varName, @NotNull Configuration configuration) {
     final ReplaceOptions replaceOptions = configuration.getReplaceOptions();
     ReplacementVariableDefinition definition = replaceOptions.getVariableDefinition(varName);
 
@@ -145,7 +146,7 @@ public final class UIUtil {
     return replaceOptions.addNewVariableDefinition(varName);
   }
 
-  public static boolean isTarget(String varName, MatchOptions matchOptions) {
+  public static boolean isTarget(@NotNull String varName, @NotNull MatchOptions matchOptions) {
     if (Configuration.CONTEXT_VAR_NAME.equals(varName)) {
       // Complete Match is default target
       for (String name : matchOptions.getVariableConstraintNames()) {
@@ -165,14 +166,14 @@ public final class UIUtil {
   }
 
   @NotNull
-  public static JComponent createCompleteMatchInfo(final Supplier<? extends Configuration> configurationProducer) {
+  public static JComponent createCompleteMatchInfo(@NotNull Supplier<? extends Configuration> configurationProducer) {
     return installCompleteMatchInfo(new JLabel(AllIcons.Actions.ListFiles), configurationProducer, null);
   }
 
   @NotNull
-  public static JComponent installCompleteMatchInfo(JLabel completeMatchInfo,
-                                                    Supplier<? extends Configuration> configurationProducer,
-                                                    Consumer<? super String> linkConsumer) {
+  public static JComponent installCompleteMatchInfo(@NotNull JLabel completeMatchInfo,
+                                                    @NotNull Supplier<? extends Configuration> configurationProducer,
+                                                    @Nullable Consumer<? super String> linkConsumer) {
     completeMatchInfo.putClientProperty(IdeTooltip.TOOLTIP_DISMISS_DELAY_KEY, 20000);
     completeMatchInfo.addMouseListener(new MouseAdapter() {
       @Override
@@ -219,27 +220,30 @@ public final class UIUtil {
     return completeMatchInfo;
   }
 
-  public static EditorTextField createTextComponent(String text, Project project) {
+  @NotNull
+  public static EditorTextField createTextComponent(@NotNull String text, @NotNull Project project) {
     return createEditorComponent(text, "1.txt", project);
   }
 
-  public static EditorTextField createRegexComponent(String text, Project project) {
+  @NotNull
+  public static EditorTextField createRegexComponent(@NotNull String text, @NotNull Project project) {
     return createEditorComponent(text, "1.regexp", project);
   }
 
-  public static EditorTextField createScriptComponent(String text, Project project) {
+  @NotNull
+  public static EditorTextField createScriptComponent(@NotNull String text, @NotNull Project project) {
     return createEditorComponent(text, "1.groovy", project);
   }
 
   @NotNull
-  public static EditorTextField createEditorComponent(String text, String fileName, Project project) {
+  public static EditorTextField createEditorComponent(@NotNull String text, @NotNull String fileName, @NotNull Project project) {
     final FileType fileType = getFileType(fileName);
     final Document document = createDocument(fileType, text, project);
     return new EditorTextField(document, project, fileType);
   }
 
   @NotNull
-  public static Document createDocument(FileType fileType, String text, Project project) {
+  public static Document createDocument(@NotNull FileType fileType, @NotNull String text, @NotNull Project project) {
     final PsiFile file =
       PsiFileFactory.getInstance(project).createFileFromText("Dummy." + fileType.getDefaultExtension(), fileType, text, -1, true);
     final Document document = PsiDocumentManager.getInstance(project).getDocument(file);
@@ -247,12 +251,14 @@ public final class UIUtil {
     return document;
   }
 
-  private static FileType getFileType(final String fileName) {
+  @NotNull
+  private static FileType getFileType(@NotNull String fileName) {
     FileType fileType = FileTypeManager.getInstance().getFileTypeByFileName(fileName);
     if (fileType == FileTypes.UNKNOWN) fileType = FileTypes.PLAIN_TEXT;
     return fileType;
   }
 
+  @NotNull
   public static LanguageFileType detectFileType(@NotNull SearchContext searchContext) {
     final PsiFile file = searchContext.getFile();
     PsiElement context = null;
@@ -275,8 +281,11 @@ public final class UIUtil {
       final Language language = context.getLanguage();
       final StructuralSearchProfile profile = StructuralSearchUtil.getProfileByLanguage(language);
       if (profile != null) {
-        final LanguageFileType fileType = profile.detectFileType(context);
-        return fileType != null ? fileType : language.getAssociatedFileType();
+        LanguageFileType fileType = profile.detectFileType(context);
+        if (fileType == null) {
+          fileType = language.getAssociatedFileType();
+        }
+        if (fileType != null) return fileType;
       }
     }
     return StructuralSearchUtil.getDefaultFileType();
@@ -329,7 +338,7 @@ public final class UIUtil {
            : factory.createFileFromText(name, dialect, text, true, true);
   }
 
-  public static TemplateContextType getTemplateContextType(StructuralSearchProfile profile) {
+  public static TemplateContextType getTemplateContextType(@NotNull StructuralSearchProfile profile) {
     final Class<? extends TemplateContextType> clazz = profile.getTemplateContextTypeClass();
     return ContainerUtil.findInstance(TemplateContextType.EP_NAME.getExtensions(), clazz);
   }

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/ui/UsageViewContext.java

@@ -18,18 +18,21 @@ import java.awt.event.ActionEvent;
 
 public class UsageViewContext {
 
+  @NotNull
   protected final SearchContext mySearchContext;
+  @NotNull
   protected final Configuration myConfiguration;
+  @NotNull
   private final ConfigurableUsageTarget myTarget;
   protected UsageView myUsageView;
 
-  protected UsageViewContext(Configuration configuration, SearchContext searchContext, Runnable searchStarter) {
+  protected UsageViewContext(@NotNull Configuration configuration, @NotNull SearchContext searchContext, @NotNull Runnable searchStarter) {
     myConfiguration = configuration;
     mySearchContext = searchContext;
     myTarget = new StructuralSearchUsageTarget(configuration, searchContext, searchStarter);
   }
 
-  public void setUsageView(final UsageView usageView) {
+  public void setUsageView(@NotNull UsageView usageView) {
     myUsageView = usageView;
     final MessageBusConnection connection = mySearchContext.getProject().getMessageBus().connect(usageView);
     connection.subscribe(DynamicPluginListener.TOPIC, new DynamicPluginListener() {
@@ -40,7 +43,7 @@ public class UsageViewContext {
     });
   }
 
-  public ConfigurableUsageTarget getTarget() {
+  public @NotNull ConfigurableUsageTarget getTarget() {
     return myTarget;
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/util/CollectingMatchResultSink.java

@@ -12,7 +12,7 @@ public class CollectingMatchResultSink extends DefaultMatchResultSink {
   private final List<MatchResult> matches = new SmartList<>();
 
   @Override
-  public void newMatch(MatchResult result) {
+  public void newMatch(@NotNull MatchResult result) {
     matches.add(result);
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/util/DuplicateFilteringResultSink.java

@@ -6,6 +6,7 @@ import com.intellij.structuralsearch.MatchResult;
 import com.intellij.structuralsearch.MatchResultSink;
 import com.intellij.structuralsearch.MatchingProcess;
 import gnu.trove.THashSet;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.Set;
 
@@ -14,14 +15,14 @@ import java.util.Set;
  */
 public class DuplicateFilteringResultSink implements MatchResultSink {
   private final MatchResultSink delegate;
-  final Set<SmartPsiPointer> duplicates = new THashSet<>();
+  private final Set<SmartPsiPointer> duplicates = new THashSet<>();
 
-  public DuplicateFilteringResultSink(MatchResultSink delegate) {
+  public DuplicateFilteringResultSink(@NotNull MatchResultSink delegate) {
     this.delegate = delegate;
   }
 
   @Override
-  public void newMatch(MatchResult result) {
+  public void newMatch(@NotNull MatchResult result) {
     if (!duplicates.add(result.getMatchRef())) {
       return;
     }
@@ -29,12 +30,12 @@ public class DuplicateFilteringResultSink implements MatchResultSink {
   }
 
   @Override
-  public void processFile(PsiFile element) {
+  public void processFile(@NotNull PsiFile element) {
     delegate.processFile(element);
   }
 
   @Override
-  public void setMatchingProcess(MatchingProcess matchingProcess) {
+  public void setMatchingProcess(@NotNull MatchingProcess matchingProcess) {
     delegate.setMatchingProcess(matchingProcess);
   }
 

platform/structuralsearch/source/com/intellij/structuralsearch/plugin/util/SmartPsiPointer.java

@@ -1,23 +1,24 @@
 package com.intellij.structuralsearch.plugin.util;
 
-import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.SmartPointerManager;
 import com.intellij.psi.SmartPsiElementPointer;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Reference to element have been matched
  */
 public class SmartPsiPointer {
-  private SmartPsiElementPointer pointer;
+  @NotNull 
+  private final SmartPsiElementPointer<?> pointer;
 
-  public SmartPsiPointer(PsiElement element) {
-    pointer = element != null ? SmartPointerManager.getInstance(element.getProject()).createSmartPsiElementPointer(element):null;
+  public SmartPsiPointer(@NotNull PsiElement element) {
+    pointer = SmartPointerManager.getInstance(element.getProject()).createSmartPsiElementPointer(element);
   }
 
   public VirtualFile getFile() {
-    return pointer != null ? pointer.getVirtualFile():null;
+    return pointer.getVirtualFile();
   }
 
   public int getOffset() {
@@ -31,16 +32,7 @@ public class SmartPsiPointer {
   }
 
   public PsiElement getElement() {
-    return pointer != null ? pointer.getElement():null;
-  }
-
-  public void clear() {
-    pointer = null;
-  }
-
-  public Project getProject() {
-    PsiElement element = getElement();
-    return element == null ? null : element.getProject();
+    return pointer.getElement();
   }
 
   public boolean equals(Object o) {

plugins/groovy/structuralsearch-groovy/src/com/intellij/structuralsearch/GroovyStructuralSearchProfile.java

@@ -53,7 +53,7 @@ public class GroovyStructuralSearchProfile extends StructuralSearchProfileBase {
   }
 
   @Override
-  public PsiCodeFragment createCodeFragment(Project project, String text, String contextId) {
+  public PsiCodeFragment createCodeFragment(@NotNull Project project, @NotNull String text, String contextId) {
     return new GroovyCodeFragment(project, text);
   }