cleanup - isEmpty

GitOrigin-RevId: 100d69abb6a423556574a72e82508fdb8f5d7fa3

RegExpSupport/src/org/intellij/lang/regexp/surroundWith/SimpleSurroundDescriptor.java

@@ -66,7 +66,7 @@ public class SimpleSurroundDescriptor implements SurroundDescriptor {
       }
     }
 
-    if (startOffset == endOffset && atoms.size() > 0) {
+    if (startOffset == endOffset && !atoms.isEmpty()) {
       PsiElement[] elements = PsiUtilCore.toPsiElementArray(atoms);
       if ((atoms.size() == 1 || PsiTreeUtil.findCommonParent(elements) == elements[0].getParent())) {
         return elements;

java/compiler/forms-compiler/src/com/intellij/uiDesigner/lw/FontDescriptor.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.uiDesigner.lw;
 
 import javax.swing.*;
@@ -49,7 +49,7 @@ public final class FontDescriptor {
       return null;
     }
     String name = myFontName;
-    if (name == null || name.length() == 0) {
+    if (name == null || name.isEmpty()) {
       if (defaultFont == null) {
         return null;
       }

java/compiler/instrumentation-util/src/com/intellij/compiler/instrumentation/InstrumentationClassFinder.java

@@ -1,4 +1,4 @@
-// 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.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.compiler.instrumentation;
 
 import org.jetbrains.org.objectweb.asm.ClassReader;
@@ -516,7 +516,7 @@ public class InstrumentationClassFinder {
         s = url.getFile();
       }
 
-      if (s != null && s.length() > 0) {
+      if (s != null && !s.isEmpty()) {
         if (Loader.JRT_PROTOCOL.equals(protocol)) {
           final Loader jrtLoader = JrtClassHolder.create(url, index);
           if (jrtLoader != null) {

java/compiler/openapi/src/com/intellij/openapi/deployment/DeploymentUtil.java

@@ -16,7 +16,7 @@ public abstract class DeploymentUtil {
   }
 
   public static String trimForwardSlashes(@NotNull String path) {
-    while (path.length() != 0 && (path.charAt(0) == '/' || path.charAt(0) == File.separatorChar)) {
+    while (!path.isEmpty() && (path.charAt(0) == '/' || path.charAt(0) == File.separatorChar)) {
       path = path.substring(1);
     }
     return path;
@@ -25,7 +25,7 @@ public abstract class DeploymentUtil {
   public static String concatPaths(String... paths) {
     final StringBuilder builder = new StringBuilder();
     for (String path : paths) {
-      if (path.length() == 0) continue;
+      if (path.isEmpty()) continue;
 
       final int len = builder.length();
       if (len > 0 && builder.charAt(len - 1) != '/' && builder.charAt(len - 1) != File.separatorChar) {
@@ -43,7 +43,7 @@ public abstract class DeploymentUtil {
     if (endsWithSlash && startsWithSlash) {
       tail = trimForwardSlashes(relativePath);
     }
-    else if (!endsWithSlash && !startsWithSlash && basePath.length() > 0 && relativePath.length() > 0) {
+    else if (!endsWithSlash && !startsWithSlash && !basePath.isEmpty() && !relativePath.isEmpty()) {
       tail = "/" + relativePath;
     }
     else {

java/execution/impl/src/com/intellij/execution/JavaTestFrameworkRunnableState.java

@@ -470,7 +470,7 @@ public abstract class JavaTestFrameworkRunnableState<T extends
         }
       }
       if (enabled) {
-        if (buf.length() > 0) buf.append(delimiter);
+        if (!buf.isEmpty()) buf.append(delimiter);
         final Class<?> classListener = listener.getClass();
         buf.append(classListener.getName());
         javaParameters.getClassPath().add(PathUtil.getJarPathForClass(classListener));

java/execution/impl/src/com/intellij/execution/MethodBrowser.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2015 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.execution;
 
 import com.intellij.codeInsight.completion.CompletionResultSet;
@@ -45,7 +31,7 @@ public abstract class MethodBrowser extends BrowseModuleValueActionListener<JCom
   @Override
   protected String showDialog() {
     final String className = getClassName();
-    if (className.trim().length() == 0) {
+    if (className.trim().isEmpty()) {
       Messages.showMessageDialog(getField(), ExecutionBundle.message("set.class.name.message"),
                                  ExecutionBundle.message("cannot.browse.method.dialog.title"), Messages.getInformationIcon());
       return null;
@@ -84,7 +70,7 @@ public abstract class MethodBrowser extends BrowseModuleValueActionListener<JCom
     @Override
     protected void addCompletionVariants(@NotNull String text, int offset, @NotNull String prefix, @NotNull CompletionResultSet result) {
       final String className = getClassName();
-      if (className.trim().length() == 0) {
+      if (className.trim().isEmpty()) {
         return;
       }
       final PsiClass testClass = getModuleSelector().findClass(className);

java/execution/impl/src/com/intellij/execution/jshell/JShellHandler.java

@@ -241,7 +241,7 @@ public final class JShellHandler {
     if (protocolJar != null) {
       launchCp.append(File.pathSeparator).append(protocolJar);
     }
-    if (launchCp.length() > 0) {
+    if (!launchCp.isEmpty()) {
       cmdLine.addParameter("-classpath");
       cmdLine.addParameter(launchCp.toString());
     }

java/execution/impl/src/com/intellij/execution/junit/RefactoringListeners.java

@@ -21,7 +21,7 @@ public final class RefactoringListeners {
     final StringBuilder path = new StringBuilder();
     for (PsiPackage parent = accessor.getPsiElement(); parent != null; parent = parent.getParentPackage()) {
       if (parent.equals(psiPackage)) return new RefactorPackage(accessor, path.toString());
-      if (path.length() > 0) path.insert(0, '.');
+      if (!path.isEmpty()) path.insert(0, '.');
       path.insert(0, parent.getName());
     }
     return null;
@@ -33,7 +33,7 @@ public final class RefactoringListeners {
     final StringBuilder path = new StringBuilder();
     for (PsiClass parent = aClass; parent != null; parent = PsiTreeUtil.getParentOfType(parent, PsiClass.class, true)) {
       if (parent.equals(psiClass)) return new RefactorClass(accessor, path.toString());
-      if (path.length() > 0) path.insert(0, '$');
+      if (!path.isEmpty()) path.insert(0, '$');
       path.insert(0, parent.getName());
     }
     return null;
@@ -104,7 +104,7 @@ public final class RefactoringListeners {
       T newElement1 = convertNewElement(newElement);
       if (newElement1 == null) return;
       String qualifiedName = getQualifiedName(newElement1);
-      if (myPath.length() > 0) {
+      if (!myPath.isEmpty()) {
         qualifiedName = qualifiedName + "." + myPath;
         newElement1 = findNewElement(newElement1, qualifiedName);
       }
@@ -258,7 +258,7 @@ public final class RefactoringListeners {
     }
 
     private String getClassQName(final String packageQName) {
-      if (packageQName.length() > 0) {
+      if (!packageQName.isEmpty()) {
         return packageQName + '.' + myInpackageName;
       }
       else {

java/execution/impl/src/com/intellij/execution/scratch/JavaScratchConfiguration.java

@@ -48,7 +48,7 @@ public class JavaScratchConfiguration extends ApplicationConfiguration {
   public void checkConfiguration() throws RuntimeConfigurationException {
     JavaParametersUtil.checkAlternativeJRE(this);
     final String className = getMainClassName();
-    if (className == null || className.length() == 0) {
+    if (className == null || className.isEmpty()) {
       throw new RuntimeConfigurationError(ExecutionBundle.message("no.main.class.specified.error.text"));
     }
     if (getScratchFileUrl() == null) {

java/execution/openapi/src/com/intellij/execution/configurations/JavaRunConfigurationModule.java

@@ -120,7 +120,7 @@ public class JavaRunConfigurationModule extends RunConfigurationModule {
   }
 
   public PsiClass checkClassName(final String className, final @NlsContexts.DialogMessage String errorMessage) throws RuntimeConfigurationException {
-    if (className == null || className.length() == 0) {
+    if (className == null || className.isEmpty()) {
       throw new RuntimeConfigurationError(errorMessage);
     }
     return findNotNullClass(className);

java/execution/openapi/src/com/intellij/execution/configurations/RemoteConnection.java

@@ -1,4 +1,4 @@
-// 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.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.execution.configurations;
 
 import com.intellij.openapi.util.text.StringUtil;
@@ -119,11 +119,11 @@ public class RemoteConnection {
     if (shmem) {
       if (serverMode) {
         result = "-Xdebug -Xrunjdwp:transport=dt_shmem,server=n,address=" +
-                 ((address.length() > 0) ? address : "...") + ",suspend=y" + ONTHROW + ONUNCAUGHT;
+                 ((!address.isEmpty()) ? address : "...") + ",suspend=y" + ONTHROW + ONUNCAUGHT;
       }
       else {
         result = "-Xdebug -Xrunjdwp:transport=dt_shmem,server=y,suspend=n,address=" +
-                 ((address.length() > 0) ? address : "...");
+                 ((!address.isEmpty()) ? address : "...");
       }
     }
     else { // socket transport

java/idea-ui/src/com/intellij/ide/projectWizard/ModuleNameLocationComponent.java

@@ -120,7 +120,7 @@ public class ModuleNameLocationComponent implements ModuleNameLocationSettings {
         }
         String path = getDefaultBaseDir(myWizardContext, namePathComponent);
         final String moduleName = getModuleName();
-        if (path.length() > 0 && !Comparing.strEqual(moduleName, namePathComponent.getNameValue())) {
+        if (!path.isEmpty() && !Comparing.strEqual(moduleName, namePathComponent.getNameValue())) {
           path += "/" + moduleName;
         }
         if (!myContentRootChangedByUser) {

java/idea-ui/src/com/intellij/ide/util/importProject/JavaModuleInsight.java

@@ -217,7 +217,7 @@ public final class JavaModuleInsight extends ModuleInsight {
     }
 
     String packageName = buffer.toString();
-    if (packageName.length() == 0 || StringUtil.endsWithChar(packageName, '.') || StringUtil.startsWithChar(packageName, '*')) {
+    if (packageName.isEmpty() || StringUtil.endsWithChar(packageName, '.') || StringUtil.startsWithChar(packageName, '*')) {
       return null;
     }
     return packageName;

java/idea-ui/src/com/intellij/ide/util/projectWizard/JavaSettingsStep.java

@@ -78,7 +78,7 @@ public class JavaSettingsStep extends SdkSettingsStep {
         if (contentEntryPath != null) {
           final String dirName = mySourcePath.getText().trim().replace(File.separatorChar, '/');
           PropertiesComponent.getInstance().setValue(MODULE_SOURCE_ROOT_KEY, dirName);
-          String text = dirName.length() > 0? contentEntryPath + "/" + dirName : contentEntryPath;
+          String text = !dirName.isEmpty() ? contentEntryPath + "/" + dirName : contentEntryPath;
           ((JavaModuleBuilder)myModuleBuilder).setSourcePaths(Collections.singletonList(Pair.create(text, "")));
         }
       }

java/idea-ui/src/com/intellij/ide/util/projectWizard/ProjectNameStep.java

@@ -97,13 +97,13 @@ public final class ProjectNameStep extends ModuleWizardStep {
   @Override
   public boolean validate() throws ConfigurationException {
     String name = myNamePathComponent.getNameValue();
-    if (name.length() == 0) {
+    if (name.isEmpty()) {
       ApplicationNamesInfo info = ApplicationNamesInfo.getInstance();
       throw new ConfigurationException(JavaUiBundle.message("prompt.new.project.file.name", info.getFullProductName(), myWizardContext.getPresentationName()));
     }
 
     final String projectFileDirectory = getProjectFileDirectory();
-    if (projectFileDirectory.length() == 0) {
+    if (projectFileDirectory.isEmpty()) {
       throw new ConfigurationException(JavaUiBundle.message("prompt.enter.project.file.location", myWizardContext.getPresentationName()));
     }
 

java/idea-ui/src/com/intellij/ide/util/projectWizard/importSources/JavaSourceRootDetectionUtil.java

@@ -79,7 +79,7 @@ public final class JavaSourceRootDetectionUtil {
       skipWhiteSpaceAndComments(lexer);
     }
     String packageName = buffer.toString();
-    if (packageName.length() == 0 || StringUtil.endsWithChar(packageName, '.')) return null;
+    if (packageName.isEmpty() || StringUtil.endsWithChar(packageName, '.')) return null;
     return packageName;
   }
 

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/AnnotationsEditor.java

@@ -91,7 +91,7 @@ public class AnnotationsEditor extends ModuleElementsEditor {
         @Override
         public void run(AnActionButton button) {
           final List<Object[]> removedItems = TableUtil.removeSelectedItems(myTable);
-          if (removedItems.size() > 0) {
+          if (!removedItems.isEmpty()) {
             saveData();
           }
         }

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/JavaResourceRootEditHandlerBase.java

@@ -54,7 +54,7 @@ public abstract class JavaResourceRootEditHandlerBase extends ModuleSourceRootEd
     if (!relativeOutputPath.isEmpty()) {
       buffer.append(" (").append(relativeOutputPath).append(")");
     }
-    return buffer.length() > 0 ? buffer.toString() : null;
+    return !buffer.isEmpty() ? buffer.toString() : null;
   }
 
   @Override

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/JavadocEditor.java

@@ -115,7 +115,7 @@ public class JavadocEditor extends ModuleElementsEditor {
         @Override
         public void run(AnActionButton button) {
           final List<Object[]> removedItems = TableUtil.removeSelectedItems(myTable);
-          if (removedItems.size() > 0) {
+          if (!removedItems.isEmpty()) {
             saveData();
           }
         }

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/ProjectConfigurable.java

@@ -126,7 +126,7 @@ public class ProjectConfigurable extends ProjectStructureElementConfigurable<Pro
       // set the output path first so that handlers of RootsChanged event sent after JDK is set
       // would see the updated path
       String canonicalPath = myUi.getProjectCompilerOutput();
-      if (canonicalPath.length() > 0) {
+      if (!canonicalPath.isEmpty()) {
         try {
           canonicalPath = FileUtil.resolveShortWindowsName(canonicalPath);
         }

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/artifacts/ArtifactEditorImpl.java

@@ -145,7 +145,7 @@ public class ArtifactEditorImpl implements ArtifactEditorEx {
 
   private @Nullable String getConfiguredOutputPath() {
     String outputPath = FileUtil.toSystemIndependentName(myOutputDirectoryField.getText().trim());
-    if (outputPath.length() == 0) {
+    if (outputPath.isEmpty()) {
       outputPath = null;
     }
     return outputPath;
@@ -472,7 +472,7 @@ public class ArtifactEditorImpl implements ArtifactEditorEx {
       final String name = ((ArchivePackagingElement)root).getArchiveFileName();
       final String fileName = FileUtilRt.getNameWithoutExtension(name);
       final String extension = FileUtilRt.getExtension(name);
-      if (fileName.equals(oldFileName) && extension.length() > 0) {
+      if (fileName.equals(oldFileName) && !extension.isEmpty()) {
         myLayoutTreeComponent.editLayout(
           () -> ((ArchivePackagingElement)getRootElement()).setArchiveFileName(ArtifactUtil.suggestArtifactFileName(newArtifactName) + "." + extension));
         myLayoutTreeComponent.updateRootNode();

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/artifacts/sourceItems/actions/PutIntoDefaultLocationActionBase.java

@@ -27,7 +27,7 @@ public abstract class PutIntoDefaultLocationActionBase extends AnAction {
     String target;
     if (paths.size() == 1) {
       final String path = StringUtil.trimStart(StringUtil.trimEnd(paths.iterator().next(), "/"), "/");
-      if (path.length() > 0) {
+      if (!path.isEmpty()) {
         target = "/" + path;
       }
       else {

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/libraryEditor/LibraryEditorDialogBase.java

@@ -51,7 +51,7 @@ public abstract class LibraryEditorDialogBase extends DialogWrapper {
 
   protected boolean validateAndApply() {
     String newName = myNameField.getText().trim();
-    if (newName.length() == 0) {
+    if (newName.isEmpty()) {
       newName = null;
     }
     if (shouldCheckName(newName)) {

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/libraryEditor/LibraryRootsComponent.java

@@ -125,7 +125,7 @@ public class LibraryRootsComponent implements Disposable, LibraryEditorComponent
       type != null ? Collections.singleton(type.getKind()) : Collections.emptySet();
     for (@Nls String description : LibraryPresentationManager.getInstance().getDescriptions(getLibraryEditor().getFiles(OrderRootType.CLASSES),
                                                                                             excluded)) {
-      if (sb.length() > 0) {
+      if (!sb.isEmpty()) {
         sb.append("\n");
       }
       sb.append(description);

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/projectRoot/BaseLibrariesConfigurable.java

@@ -265,7 +265,7 @@ public abstract class BaseLibrariesConfigurable extends BaseStructureConfigurabl
           final LibraryProjectStructureElement libraryElement = new LibraryProjectStructureElement(myContext, library);
           final Collection<ProjectStructureElementUsage> usages =
             new ArrayList<>(myContext.getDaemonAnalyzer().getUsages(libraryElement));
-          if (usages.size() > 0) {
+          if (!usages.isEmpty()) {
             if (librariesWithUsages == 0) {
               final MultiMap<String, ProjectStructureElementUsage> containerType2Usage = new MultiMap<>();
               for (final ProjectStructureElementUsage usage : usages) {

java/idea-ui/src/com/intellij/projectImport/ProjectImportWizardStep.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2009 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.projectImport;
 
 import com.intellij.ide.util.projectWizard.ModuleWizardStep;
@@ -42,7 +28,7 @@ public abstract class ProjectImportWizardStep extends ModuleWizardStep {
   }
 
   protected void suggestProjectNameAndPath(final String alternativePath, final String path) {
-    getWizardContext().setProjectFileDirectory(alternativePath != null && alternativePath.length() > 0 ? alternativePath : path);
+    getWizardContext().setProjectFileDirectory(alternativePath != null && !alternativePath.isEmpty() ? alternativePath : path);
     final String global = FileUtil.toSystemIndependentName(path);
     getWizardContext().setProjectName(global.substring(global.lastIndexOf("/") + 1));
   }

java/idea-ui/src/com/intellij/projectImport/SelectImportedProjectsStep.java

@@ -104,7 +104,7 @@ public abstract class SelectImportedProjectsStep<T> extends ProjectImportWizardS
   @Override
   public boolean validate() throws ConfigurationException {
     getContext().setList(fileChooser.getMarkedElements());
-    if (fileChooser.getMarkedElements().size() == 0) {
+    if (fileChooser.getMarkedElements().isEmpty()) {
       throw new ConfigurationException(JavaUiBundle.message("select.imported.projects.dialog.message.nothing.found"),
                                        JavaUiBundle.message("select.imported.projects.dialog.title.unable.to.proceed"));
     }

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/inference/ContractInferenceInterpreter.java

@@ -380,7 +380,7 @@ class ContractInferenceInterpreter {
         List<PreContract> conditionResults = visitExpression(states, findExpressionChild(myTree, statement));
 
         List<LighterASTNode> thenElse = getStatements(statement, myTree);
-        if (thenElse.size() > 0) {
+        if (!thenElse.isEmpty()) {
           result.addAll(visitStatements(antecedentsReturning(conditionResults, returnTrue()), singletonList(thenElse.get(0))));
         }
 

java/java-analysis-impl/src/com/intellij/codeInspection/java19modules/JavaModuleNamingInspection.java

@@ -25,7 +25,7 @@ public final class JavaModuleNamingInspection extends AbstractBaseJavaLocalInspe
         Ref<String> newName = Ref.create();
         psiTraverser().children(name).filter(PsiIdentifier.class).forEach(id -> {
           String text = id.getText();
-          if (text.length() > 0 && Character.isDigit(text.charAt(text.length() - 1))) {
+          if (!text.isEmpty() && Character.isDigit(text.charAt(text.length() - 1))) {
             String message = JavaAnalysisBundle.message("inspection.java.module.naming.terminal.digits", text);
             if (newName.isNull()) {
               newName.set(StringUtil.join(psiTraverser().children(name).filter(PsiIdentifier.class).map(i -> trimDigits(i.getText())), "."));

java/java-analysis-impl/src/com/intellij/openapi/roots/impl/JavaModuleExternalPathsImpl.java

@@ -127,7 +127,7 @@ public final class JavaModuleExternalPathsImpl extends JavaModuleExternalPaths {
     List<Element> toWrite = null;
     for (OrderRootType orderRootType : myOrderRootPointerContainers.keySet()) {
       VirtualFilePointerContainer container = myOrderRootPointerContainers.get(orderRootType);
-      if (container != null && container.size() > 0) {
+      if (container != null && !container.isEmpty()) {
         final Element content = new Element(((PersistentOrderRootType)orderRootType).getModulePathsName());
         container.writeExternal(content, ROOT_ELEMENT, false);
         if (toWrite == null) {

java/java-analysis-impl/src/com/siyeh/ig/controlflow/BreakStatementWithLabelInspection.java

@@ -51,7 +51,7 @@ public final class BreakStatementWithLabelInspection extends BaseInspection {
       if (labelText == null) {
         return;
       }
-      if (labelText.length() == 0) {
+      if (labelText.isEmpty()) {
         return;
       }
       registerStatementError(statement);

java/java-analysis-impl/src/com/siyeh/ig/controlflow/ContinueStatementWithLabelInspection.java

@@ -50,7 +50,7 @@ public final class ContinueStatementWithLabelInspection extends BaseInspection {
       if (labelText == null) {
         return;
       }
-      if (labelText.length() == 0) {
+      if (labelText.isEmpty()) {
         return;
       }
       registerStatementError(statement);

java/java-analysis-impl/src/com/siyeh/ig/numeric/ImplicitNumericConversionInspection.java

@@ -224,7 +224,7 @@ public final class ImplicitNumericConversionInspection extends BaseInspection {
 
     private static boolean isDecimalLiteral(String text) {
       // should not be binary, octal or hexadecimal: 0b101, 077, 0xFF
-      return text.length() > 0 && text.charAt(0) != '0';
+      return !text.isEmpty() && text.charAt(0) != '0';
     }
 
     private static boolean isNegatedLiteral(PsiExpression expression) {

java/java-analysis-impl/src/com/siyeh/ig/psiutils/CommentTracker.java

@@ -152,7 +152,7 @@ public final class CommentTracker {
     StringBuilder sb = new StringBuilder();
     for (PsiElement comment : comments) {
       PsiElement prev = comment.getPrevSibling();
-      if (sb.length() == 0 && prev instanceof PsiWhiteSpace) {
+      if (sb.isEmpty() && prev instanceof PsiWhiteSpace) {
         sb.append(prev.getText());
       }
       sb.append(comment.getText());

java/java-analysis-impl/src/com/siyeh/ig/psiutils/MethodUtils.java

@@ -368,7 +368,7 @@ public final class MethodUtils {
     } else {
       expressions = List.of(bodyExpression);
     }
-    if (expressions.size() == 0) return true;
+    if (expressions.isEmpty()) return true;
     for (UExpression expression : expressions) {
       ProgressManager.checkCanceled();
       if (expression instanceof UastEmptyExpression || trivialPredicate != null && trivialPredicate.test(expression)) continue;

java/java-impl-inspections/src/com/intellij/codeInspection/classCanBeRecord/RecordBuilder.java

@@ -169,7 +169,7 @@ class RecordBuilder {
   }
 
   private void trimEndingWhiteSpaces() {
-    if (myRecordText.length() == 0) return;
+    if (myRecordText.isEmpty()) return;
     int endIndex = myRecordText.length() - 1;
     if (myRecordText.charAt(endIndex) != ' ') return;
 

java/java-impl-inspections/src/com/intellij/codeInspection/reflectiveAccess/JavaLangReflectHandleInvocationChecker.java

@@ -145,7 +145,7 @@ final class JavaLangReflectHandleInvocationChecker {
     final List<Supplier<ReflectiveType>> lazyMethodSignature = getLazyMethodSignature(signatureExpression);
     if (lazyMethodSignature == null) return true;
 
-    if (!isConstructor && lazyMethodSignature.size() != 0) {
+    if (!isConstructor && !lazyMethodSignature.isEmpty()) {
       final ReflectiveType returnType = lazyMethodSignature.get(0).get();
       checkReturnType(invokeCall, returnType, isExact, holder);
     }

java/java-impl-inspections/src/com/intellij/codeInspection/streamMigration/JoiningMigration.java

@@ -901,7 +901,7 @@ public class JoiningMigration extends BaseStreamApiMigration {
                                                                                    @Nullable List<PsiVariable> nonFinalVariables) {
         if (nonFinalVariables != null && !nonFinalVariables.isEmpty()) return null;
         List<PsiStatement> statements = Arrays.asList(terminalBlock.getStatements());
-        if (statements.size() < 1) return null;
+        if (statements.isEmpty()) return null;
         PsiVariable targetBuilder = extractStringBuilder(statements.get(0));
         if(!(targetBuilder instanceof PsiLocalVariable)) return null;
         List<PsiExpression> joinParts = extractJoinParts(statements);
@@ -1285,7 +1285,7 @@ public class JoiningMigration extends BaseStreamApiMigration {
           delimiterJoinParts.add(joinPart);
           sb.append(constantExpression);
         }
-        String separator = sb.length() == 0 ? null : sb.toString();
+        String separator = sb.isEmpty() ? null : sb.toString();
         if (firstNonConstant != -1) {
           List<PsiExpression> mainJoinParts = joinParts.subList(firstNonConstant, joinParts.size());
           return new JoinData(separator, mainJoinParts, delimiterJoinParts);
@@ -1307,7 +1307,7 @@ public class JoiningMigration extends BaseStreamApiMigration {
           sb.append(constantExpression);
           delimiterJoinParts.add(joinPart);
         }
-        String separator = sb.length() == 0 ? null : sb.toString();
+        String separator = sb.isEmpty() ? null : sb.toString();
         if (firstNonConstant != -1) {
           List<PsiExpression> mainJoinParts = joinParts.subList(0, firstNonConstant + 1);
           return new JoinData(separator, mainJoinParts, delimiterJoinParts);

java/java-impl-refactorings/src/com/intellij/refactoring/copy/CopyClassDialog.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.refactoring.copy;
 
 import com.intellij.CommonBundle;
@@ -148,7 +148,7 @@ class CopyClassDialog extends RefactoringDialog implements DumbAware {
     final String[] errorString = new String[1];
     final PsiManager manager = PsiManager.getInstance(myProject);
     final PsiNameHelper nameHelper = PsiNameHelper.getInstance(manager.getProject());
-    if (packageName.length() > 0 && !nameHelper.isQualifiedName(packageName)) {
+    if (!packageName.isEmpty() && !nameHelper.isQualifiedName(packageName)) {
       errorString[0] = JavaRefactoringBundle.message("invalid.target.package.name.specified");
     } else if (className != null && className.isEmpty()) {
       errorString[0] = JavaRefactoringBundle.message("no.class.name.specified");
@@ -170,7 +170,7 @@ class CopyClassDialog extends RefactoringDialog implements DumbAware {
     }
 
     if (errorString[0] != null) {
-      if (errorString[0].length() > 0) {
+      if (!errorString[0].isEmpty()) {
         Messages.showMessageDialog(myProject, errorString[0], RefactoringBundle.message("error.title"), Messages.getErrorIcon());
       }
       myNameField.requestFocusInWindow();

java/java-impl-refactorings/src/com/intellij/refactoring/copy/CopyClassesHandler.java

@@ -105,7 +105,7 @@ public final class CopyClassesHandler extends CopyHandlerDelegateBase implements
           if (element instanceof PsiDirectory) {
             if (!fromUpdate) {
               final String name = ((PsiDirectory)element).getName();
-              final String path = relativePath != null ? (relativePath.length() > 0 ? (relativePath + "/") : "") + name : null;
+              final String path = relativePath != null ? (!relativePath.isEmpty() ? (relativePath + "/") : "") + name : null;
               final Map<PsiFile, PsiClass[]> map = convertToTopLevelClasses(element.getChildren(), false, path, relativeMap);
               if (map == null) return null;
               for (Map.Entry<PsiFile, PsiClass[]> entry : map.entrySet()) {
@@ -212,7 +212,7 @@ public final class CopyClassesHandler extends CopyHandlerDelegateBase implements
         openInEditor = dialog.isOpenInEditor();
         targetDirectory = dialog.getTargetDirectory();
         className = dialog.getClassName();
-        if (className == null || className.length() == 0) return;
+        if (className == null || className.isEmpty()) return;
       }
     }
     else {

java/java-impl-refactorings/src/com/intellij/refactoring/extractMethod/ExtractMethodDialog.java

@@ -601,7 +601,7 @@ public class ExtractMethodDialog extends RefactoringDialog implements AbstractEx
     final int declarationOffset = buffer.length();
     final String visibilityString = VisibilityUtil.getVisibilityString(getVisibility());
     buffer.append(visibilityString);
-    if (buffer.length() > 0) {
+    if (!buffer.isEmpty()) {
       buffer.append(" ");
     }
     if (isMakeStatic() && !isChainedConstructor()) {

java/java-impl-refactorings/src/com/intellij/refactoring/extractMethodObject/ExtractMethodObjectDialog.java

@@ -317,7 +317,7 @@ public class ExtractMethodObjectDialog extends DialogWrapper implements Abstract
     final String visibilityString = VisibilityUtil.getVisibilityString(getVisibility());
     if (myCreateInnerClassRb.isSelected()) {
       buffer.append(visibilityString);
-      if (buffer.length() > 0) {
+      if (!buffer.isEmpty()) {
         buffer.append(" ");
       }
       if (isMakeStatic()) {

java/java-impl-refactorings/src/com/intellij/refactoring/extractclass/ExtractClassDialog.java

@@ -160,7 +160,7 @@ class ExtractClassDialog extends RefactoringDialog implements MemberInfoChangeLi
     }
 
     final String className = getClassName();
-    if (className.length() == 0 || !nameHelper.isIdentifier(className)) {
+    if (className.isEmpty() || !nameHelper.isIdentifier(className)) {
       throw new ConfigurationException(JavaBundle.message("invalid.extracted.class.name", className));
     }
 

java/java-impl-refactorings/src/com/intellij/refactoring/extractclass/ExtractClassProcessor.java

@@ -220,7 +220,7 @@ public class ExtractClassProcessor extends FixableUsagesRefactoringProcessor {
     final Project project = sourceClass.getProject();
     final JavaCodeStyleSettings settings = JavaCodeStyleSettings.getInstance(sourceClass.getContainingFile());
 
-    final String baseName = settings.FIELD_NAME_PREFIX.length() == 0 ? StringUtil.decapitalize(newClassName) : newClassName;
+    final String baseName = settings.FIELD_NAME_PREFIX.isEmpty() ? StringUtil.decapitalize(newClassName) : newClassName;
     String name = settings.FIELD_NAME_PREFIX + baseName + settings.FIELD_NAME_SUFFIX;
     if (!existsFieldWithName(name) && !PsiNameHelper.getInstance(project).isKeyword(name)) {
       return name;
@@ -429,7 +429,7 @@ public class ExtractClassProcessor extends FixableUsagesRefactoringProcessor {
     final CodeStyleManager codeStyleManager = CodeStyleManager.getInstance(manager.getProject());
     final @NonNls StringBuilder fieldBuffer = new StringBuilder();
     final String delegateVisibility = calculateDelegateVisibility();
-    if (delegateVisibility.length() > 0) fieldBuffer.append(delegateVisibility).append(' ');
+    if (!delegateVisibility.isEmpty()) fieldBuffer.append(delegateVisibility).append(' ');
     fieldBuffer.append("final ");
     final String fullyQualifiedName = getQualifiedName();
     fieldBuffer.append(fullyQualifiedName);

java/java-impl-refactorings/src/com/intellij/refactoring/extractclass/ExtractedClassBuilder.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.refactoring.extractclass;
 
 import com.intellij.codeInsight.generation.GenerateMembersUtil;
@@ -89,7 +89,7 @@ class ExtractedClassBuilder {
       calculateBackpointerName();
     }
     final @NonNls StringBuilder out = new StringBuilder(1024);
-    if (packageName.length() > 0) out.append("package ").append(packageName).append(";\n");
+    if (!packageName.isEmpty()) out.append("package ").append(packageName).append(";\n");
 
     out.append("public ");
     fields.removeAll(enumConstantFields);

java/java-impl-refactorings/src/com/intellij/refactoring/inline/InlineMethodProcessor.java

@@ -579,7 +579,7 @@ public class InlineMethodProcessor extends BaseRefactoringProcessor {
         System.arraycopy(instanceCreationArguments, 0, exprs, 0, parameters.length - 1);
         StringBuilder varargs = new StringBuilder();
         for (int i = parameters.length - 1; i < instanceCreationArguments.length; i++) {
-          if (varargs.length() > 0) varargs.append(", ");
+          if (!varargs.isEmpty()) varargs.append(", ");
           varargs.append(instanceCreationArguments[i].getText());
         }
 

java/java-impl-refactorings/src/com/intellij/refactoring/introduceparameterobject/IntroduceParameterObjectDialog.java

@@ -210,20 +210,20 @@ public class IntroduceParameterObjectDialog extends AbstractIntroduceParameterOb
         JavaRefactoringBundle.message("introduce.parameter.object.error.inner.class.already.exist", innerClassName));
     } else if (!useExistingClass()) {
       final String className = getClassName();
-      if (className.length() == 0 || !nameHelper.isIdentifier(className)) {
+      if (className.isEmpty() || !nameHelper.isIdentifier(className)) {
         throw new ConfigurationException(
           JavaRefactoringBundle.message("introduce.parameter.object.error.invalid.parameter.class.name", className));
       }
       final String packageName = getPackageName();
 
-      if (packageName.length() == 0 || !nameHelper.isQualifiedName(packageName)) {
+      if (packageName.isEmpty() || !nameHelper.isQualifiedName(packageName)) {
         throw new ConfigurationException(
           JavaRefactoringBundle.message("introduce.parameter.object.error.invalid.parameter.class.package.name", packageName));
       }
     }
     else {
       final String className = getExistingClassName();
-      if (className.length() == 0 || !nameHelper.isQualifiedName(className)) {
+      if (className.isEmpty() || !nameHelper.isQualifiedName(className)) {
         throw new ConfigurationException(
           JavaRefactoringBundle.message("introduce.parameter.object.error.invalid.qualified.parameter.class.name", className));
       }

java/java-impl-refactorings/src/com/intellij/refactoring/introduceparameterobject/ParameterObjectBuilder.java

@@ -66,7 +66,7 @@ class ParameterObjectBuilder {
     boolean recordsAvailable = PsiUtil.isAvailable(JavaFeature.RECORDS, myFile) &&
                                !ContainerUtil.exists(fields, ParameterSpec::isSetterRequired);
     final @NonNls StringBuilder out = new StringBuilder(1024);
-    if (packageName.length() > 0) out.append("package ").append(packageName).append(';');
+    if (!packageName.isEmpty()) out.append("package ").append(packageName).append(';');
     out.append('\n');
     out.append(myVisibility).append(" ");
     out.append(recordsAvailable ? PsiKeyword.RECORD : PsiKeyword.CLASS);

java/java-impl-refactorings/src/com/intellij/refactoring/move/moveClassesOrPackages/MoveClassesOrPackagesDialog.java

@@ -128,7 +128,7 @@ public class MoveClassesOrPackagesDialog extends MoveDialogBase {
 
     myTargetDirectoryFixed = initialTargetDirectory == null;
     mySuggestToMoveToAnotherRoot = initialTargetElement == null;
-    if (targetPackageName.length() != 0) {
+    if (!targetPackageName.isEmpty()) {
       myWithBrowseButtonReference.prependItem(targetPackageName);
       myClassPackageChooser.prependItem(targetPackageName);
     }
@@ -316,7 +316,7 @@ public class MoveClassesOrPackagesDialog extends MoveDialogBase {
   protected void canRun() throws ConfigurationException {
     if (isMoveToPackage()) {
       String name = getTargetPackage().trim();
-      if (name.length() != 0 && !PsiNameHelper.getInstance(myManager.getProject()).isQualifiedName(name)) {
+      if (!name.isEmpty() && !PsiNameHelper.getInstance(myManager.getProject()).isQualifiedName(name)) {
         throw new ConfigurationException(JavaBundle.message("move.classes.invalid.destination.package.name.message", name));
       }
     }
@@ -472,7 +472,7 @@ public class MoveClassesOrPackagesDialog extends MoveDialogBase {
 
   private @Nullable MoveDestination selectDestination() {
     final String packageName = getTargetPackage().trim();
-    if (packageName.length() > 0 && !PsiNameHelper.getInstance(myManager.getProject()).isQualifiedName(packageName)) {
+    if (!packageName.isEmpty() && !PsiNameHelper.getInstance(myManager.getProject()).isQualifiedName(packageName)) {
       Messages.showErrorDialog(myProject, JavaRefactoringBundle.message("please.enter.a.valid.target.package.name"),
                                RefactoringBundle.message("move.title"));
       return null;

java/java-impl-refactorings/src/com/intellij/refactoring/move/moveInner/MoveInnerDialog.java

@@ -278,7 +278,7 @@ public class MoveInnerDialog extends MoveDialogBase {
 
         if (message == null) {
           final String packageName = getPackageName();
-          if (packageName.length() > 0 && !PsiNameHelper.getInstance(myProject).isQualifiedName(packageName)) {
+          if (!packageName.isEmpty() && !PsiNameHelper.getInstance(myProject).isQualifiedName(packageName)) {
             message = RefactoringMessageUtil.getIncorrectIdentifierMessage(packageName);
           }
         }

java/java-impl-refactorings/src/com/intellij/refactoring/move/moveMembers/MoveMembersDialog.java

@@ -226,7 +226,7 @@ public class MoveMembersDialog extends MoveDialogBase implements MoveMembersOpti
     String message = validateInputData();
 
     if (message != null) {
-      if (message.length() != 0) {
+      if (!message.isEmpty()) {
         CommonRefactoringUtil.showErrorMessage(
           MoveMembersImpl.getRefactoringName(),
           message,

java/java-impl-refactorings/src/com/intellij/refactoring/rename/JavaNameSuggestionProvider.java

@@ -104,7 +104,7 @@ public final class JavaNameSuggestionProvider implements NameSuggestionProvider
     StringBuilder buffer = new StringBuilder(prefix);
     for (int i = 0; i < words.length; i++) {
       String word = words[i];
-      final boolean prefixRequiresCapitalization = prefix.length() > 0 && !StringUtil.endsWithChar(prefix, '_');
+      final boolean prefixRequiresCapitalization = !prefix.isEmpty() && !StringUtil.endsWithChar(prefix, '_');
       if (i > 0 || prefixRequiresCapitalization) {
         buffer.append(StringUtil.capitalize(word));
       }

java/java-impl-refactorings/src/com/intellij/refactoring/rename/PsiPackageRenameValidator.java

@@ -30,7 +30,7 @@ public final class PsiPackageRenameValidator implements RenameInputValidatorEx {
       return JavaBundle.message("rename.package.ignored.name.warning");
     }
 
-    if (newName.length() > 0) {
+    if (!newName.isEmpty()) {
       if (!PsiDirectoryFactory.getInstance(project).isValidPackageName(newName)) {
         return JavaBundle.message("rename.package.invalid.name.error");
       }

java/java-impl-refactorings/src/com/intellij/refactoring/rename/naming/PsiNamedElementAutomaticRenamer.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2009 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.refactoring.rename.naming;
 
 import com.intellij.openapi.diagnostic.Logger;
@@ -37,7 +23,7 @@ public abstract class PsiNamedElementAutomaticRenamer<T extends PsiNamedElement>
     String elementName = getName(element);
     final NameSuggester suggester = new NameSuggester(getOldName(), getNewName());
     final String newCanonicalName = suggester.suggestName(elementName);
-    if (newCanonicalName.length() == 0) {
+    if (newCanonicalName.isEmpty()) {
       LOG.error("oldName = " + getOldName() + ", newName = " + getNewName() + ", name = " + elementName + ", canonicalName = " +
                 elementName + ", newCanonicalName = " + newCanonicalName);
     }

java/java-impl-refactorings/src/com/intellij/refactoring/util/classMembers/InterfaceMemberDependencyGraph.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.refactoring.util.classMembers;
 
 import com.intellij.openapi.util.NlsContexts;
@@ -77,7 +63,7 @@ public class InterfaceMemberDependencyGraph<T extends PsiMember, M extends Membe
 
   public @NlsContexts.Tooltip String getElementTooltip(PsiMember member) {
     final Set<? extends PsiMember> dependencies = getDependenciesOf(member);
-    if(dependencies == null || dependencies.size() == 0) return null;
+    if(dependencies == null || dependencies.isEmpty()) return null;
     String interfaces = StringUtil.join(dependencies, PsiMember::getName, ", ");
     return RefactoringBundle.message("interface.member.dependency.required.by.interfaces.list", dependencies.size(), interfaces);
   }

java/java-impl-refactorings/src/com/intellij/refactoring/util/duplicates/MatchUtil.java

@@ -20,7 +20,7 @@ public final class MatchUtil {
     if (!match.myChangedParams.isEmpty() || returnType != null) {
       @NonNls StringBuilder buffer = new StringBuilder();
       buffer.append(visibility);
-      if (buffer.length() > 0) {
+      if (!buffer.isEmpty()) {
         buffer.append(" ");
       }
       if (shouldBeStatic) {

java/java-impl-refactorings/src/com/intellij/refactoring/util/occurrences/ExpressionOccurrenceManager.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.refactoring.util.occurrences;
 
 import com.intellij.codeInsight.CodeInsightUtil;
@@ -69,7 +69,7 @@ public class ExpressionOccurrenceManager extends BaseOccurrenceManager {
       findModel.setCaseSensitive(true);
       findModel.setRegularExpressions(false);
       String value = StringUtil.unquoteString(myMainOccurence.getText());
-      if (value.length() > 0) {
+      if (!value.isEmpty()) {
         findModel.setStringToFind(value);
         final List<PsiExpression> results = new ArrayList<>();
         final PsiFile file = getScope().getContainingFile();

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/StaticMembersProcessor.java

@@ -162,7 +162,7 @@ abstract class StaticMembersProcessor<T extends PsiMember & PsiDocCommentOwner>
       }
 
       ApplicableType type = isApplicable(member, myPlace);
-      if (list.size() > 0) {
+      if (!list.isEmpty()) {
         Pair<T, ApplicableType> previousPair = list.get(list.size() - 1);
         if (previousPair.getFirst().getContainingClass() == containingClass &&
             previousPair.getSecond().ordinal() < type.ordinal()) {

java/java-impl/src/com/intellij/codeInsight/intention/impl/singlereturn/FinishMarker.java

@@ -141,7 +141,7 @@ public final class FinishMarker {
     List<PsiExpression> nonTerminalReturns = StreamEx.<PsiReturnStatement>of(returns).without(terminalReturn)
       .map(PsiReturnStatement::getReturnValue)
       .map(PsiUtil::skipParenthesizedExprDown).toList();
-    if (nonTerminalReturns.size() == 0) {
+    if (nonTerminalReturns.isEmpty()) {
       return new FinishMarker(FinishMarkerType.SEPARATE_VAR, null);
     }
     Set<Object> nonTerminalReturnValues = StreamEx.of(nonTerminalReturns)

java/java-impl/src/com/intellij/codeInsight/template/PsiTypeResult.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2009 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.codeInsight.template;
 
 import com.intellij.codeInsight.template.impl.JavaTemplateUtil;
@@ -42,7 +28,7 @@ public class PsiTypeResult implements RecalculatableResult {
 
   @Override
   public boolean equalsToText(String text, PsiElement context) {
-    if (text.length() == 0) return false;
+    if (text.isEmpty()) return false;
     final PsiType type = getType();
     if (text.equals(toString())) return true;
     try {

java/java-impl/src/com/intellij/codeInsight/template/macro/DescendantClassesEnumMacro.java

@@ -32,7 +32,7 @@ public final class DescendantClassesEnumMacro extends Macro {
   @Override
   public Result calculateResult(Expression @NotNull [] params, ExpressionContext context) {
     final List<PsiClass> classes = findDescendants(context, params);
-    if (classes == null || classes.size() == 0) return null;
+    if (classes == null || classes.isEmpty()) return null;
     Result[] results = calculateResults(classes);
 
     return results[0];
@@ -84,7 +84,7 @@ public final class DescendantClassesEnumMacro extends Macro {
   @Override
   public Result calculateQuickResult(Expression @NotNull [] params, ExpressionContext context) {
     final List<PsiClass> classes = findDescendants(context, params);
-    if (classes == null || classes.size() == 0) return null;
+    if (classes == null || classes.isEmpty()) return null;
     Result[] results = calculateResults(classes);
 
     return results[0];
@@ -93,14 +93,14 @@ public final class DescendantClassesEnumMacro extends Macro {
   @Override
   public LookupElement[] calculateLookupItems(Expression @NotNull [] params, ExpressionContext context) {
     final List<PsiClass> classes = findDescendants(context, params);
-    if (classes == null || classes.size() == 0) return null;
+    if (classes == null || classes.isEmpty()) return null;
 
     Set<LookupElement> set = new LinkedHashSet<>();
     boolean isShortName = params.length > 1 && !Boolean.parseBoolean(params[1].calculateResult(context).toString());
 
     for (PsiClass object : classes) {
       final String name = isShortName ? object.getName() : object.getQualifiedName();
-      if (name != null && name.length() > 0) {
+      if (name != null && !name.isEmpty()) {
         set.add(LookupElementBuilder.create(name));
       }
     }

java/java-impl/src/com/intellij/cyclicDependencies/ui/CyclicDependenciesPanel.java

@@ -34,8 +34,8 @@ import javax.swing.tree.TreeNode;
 import javax.swing.tree.TreePath;
 import javax.swing.tree.TreeSelectionModel;
 import java.awt.*;
-import java.util.List;
 import java.util.*;
+import java.util.List;
 
 public final class CyclicDependenciesPanel extends JPanel implements Disposable, UiDataProvider {
   private static final Set<PsiFile> EMPTY_FILE_SET = new HashSet<>(0);
@@ -155,7 +155,7 @@ public final class CyclicDependenciesPanel extends JPanel implements Disposable,
 
   private static PackageDependenciesNode hideEmptyMiddlePackages(PackageDependenciesNode node, StringBuffer result){
     if (node.getChildCount() == 0 || node.getChildCount() > 1 || node.getChildCount() == 1 && node.getChildAt(0) instanceof FileNode){
-      result.append(result.length() != 0 ? "." : "").append(node.toString().equals(getDefaultPackageAbbreviation()) ? "" : node.toString());//toString()
+      result.append(!result.isEmpty() ? "." : "").append(node.toString().equals(getDefaultPackageAbbreviation()) ? "" : node.toString());//toString()
     } else {
       if (node.getChildCount() == 1){
         PackageDependenciesNode child = (PackageDependenciesNode)node.getChildAt(0);
@@ -166,7 +166,7 @@ public final class CyclicDependenciesPanel extends JPanel implements Disposable,
         } else {
           if (child instanceof PackageNode){
             node.removeAllChildren();
-            result.append(result.length() != 0 ? "." : "")
+            result.append(!result.isEmpty() ? "." : "")
               .append(node.toString().equals(getDefaultPackageAbbreviation()) ? "" : node.toString());
             node = hideEmptyMiddlePackages(child, result);
             ((PackageNode)node).setPackageName(result.toString());//toString()

java/java-impl/src/com/intellij/ide/actions/JavaQualifiedNameProvider.java

@@ -170,7 +170,7 @@ public final class JavaQualifiedNameProvider implements QualifiedNameProvider {
       PsiClass aClass = member.getContainingClass();
       String className = aClass == null ? "" : aClass.getQualifiedName();
       toInsert = className == null ? "" : className;
-      if (toInsert.length() != 0) toInsert += "#";
+      if (!toInsert.isEmpty()) toInsert += "#";
       toInsert += member.getName();
       if (member instanceof PsiMethod) {
         toInsert += getParameterString((PsiMethod)member, true);
@@ -203,7 +203,8 @@ public final class JavaQualifiedNameProvider implements QualifiedNameProvider {
           // pasting reference to default constructor of the class after new
           suffix = "()";
         }
-        else if (toInsert != null && toInsert.length() != 0 && Character.isJavaIdentifierPart(toInsert.charAt(toInsert.length()-1)) && Character.isJavaIdentifierPart(elementAtCaret.getText().charAt(0))) {
+        else if (toInsert != null &&
+                 !toInsert.isEmpty() && Character.isJavaIdentifierPart(toInsert.charAt(toInsert.length()-1)) && Character.isJavaIdentifierPart(elementAtCaret.getText().charAt(0))) {
           //separate identifiers with space
           suffix = " ";
         }

java/java-impl/src/com/intellij/ide/fileTemplates/JavaCreateFromTemplateHandler.java

@@ -72,7 +72,7 @@ public class JavaCreateFromTemplateHandler implements CreateFromTemplateHandler
     if (!template.isTemplateOfType(JavaFileType.INSTANCE)) return;
 
     String packageName = (String)props.get(FileTemplate.ATTRIBUTE_PACKAGE_NAME);
-    if(packageName == null || packageName.length() == 0 || packageName.equals(FileTemplate.ATTRIBUTE_PACKAGE_NAME)){
+    if(packageName == null || packageName.isEmpty() || packageName.equals(FileTemplate.ATTRIBUTE_PACKAGE_NAME)){
       PsiPackageStatement packageStatement = file.getPackageStatement();
       if (packageStatement != null) {
         packageStatement.delete();
@@ -120,7 +120,7 @@ public class JavaCreateFromTemplateHandler implements CreateFromTemplateHandler
   @Override
   public void prepareProperties(@NotNull Map<String, Object> props) {
     String packageName = (String)props.get(FileTemplate.ATTRIBUTE_PACKAGE_NAME);
-    if (packageName == null || packageName.length() == 0) {
+    if (packageName == null || packageName.isEmpty()) {
       props.put(FileTemplate.ATTRIBUTE_PACKAGE_NAME, FileTemplate.ATTRIBUTE_PACKAGE_NAME);
     }
   }

java/java-impl/src/com/intellij/ide/fileTemplates/SaveJavaAsTemplateHandler.java

@@ -14,7 +14,7 @@ public final class SaveJavaAsTemplateHandler implements SaveFileAsTemplateHandle
   public @Nullable String getTemplateText(final PsiFile psiFile, String fileText, String nameWithoutExtension) {
     if(psiFile instanceof PsiJavaFile javaFile){
       String packageName = javaFile.getPackageName();
-      if (packageName.length() > 0){
+      if (!packageName.isEmpty()){
         fileText = StringUtil.replace(fileText, packageName, "${PACKAGE_NAME}");
       }
       PsiClass[] classes = javaFile.getClasses();

java/java-impl/src/com/intellij/internal/GenerateVisitorByHierarchyAction.java

@@ -35,8 +35,8 @@ import org.jetbrains.annotations.NotNull;
 import javax.swing.*;
 import javax.swing.event.DocumentEvent;
 import java.awt.*;
-import java.util.List;
 import java.util.*;
+import java.util.List;
 
 final class GenerateVisitorByHierarchyAction extends AnAction {
 
@@ -126,7 +126,7 @@ final class GenerateVisitorByHierarchyAction extends AnAction {
     dialog.show();
     if (dialog.getExitCode() != DialogWrapper.OK_EXIT_CODE ||
         dialog.getSelectedPackage() == null ||
-        dialog.getSelectedPackage().getQualifiedName().length() == 0 ||
+        dialog.getSelectedPackage().getQualifiedName().isEmpty() ||
         parentClassRef.isNull()) {
       return;
     }

java/java-impl/src/com/intellij/jarRepository/services/artifactory/ArtifactoryRepositoryService.java

@@ -68,7 +68,7 @@ public class ArtifactoryRepositoryService extends MavenRepositoryService {
 
 
       final String className = template.getClassNames();
-      if (className == null || className.length() == 0) {
+      if (className == null || className.isEmpty()) {
         return searchArtifacts(url, template);
       }
       else {

java/java-impl/src/com/intellij/javadoc/JavadocConfigurable.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.javadoc;
 
 import com.intellij.openapi.options.Configurable;
@@ -133,7 +133,7 @@ public final class JavadocConfigurable implements Configurable {
   }
 
   private static String toSystemIndependentFormat(String directory) {
-    if (directory.length() == 0) {
+    if (directory.isEmpty()) {
       return null;
     }
     return directory.replace(File.separatorChar, '/');

java/java-impl/src/com/intellij/javadoc/JavadocGeneratorRunProfile.java

@@ -145,7 +145,7 @@ public final class JavadocGeneratorRunProfile implements ModuleRunProfile {
       }
       cmdLine.setExePath(tool.getPath());
 
-      if (myConfiguration.HEAP_SIZE != null && myConfiguration.HEAP_SIZE.trim().length() != 0) {
+      if (myConfiguration.HEAP_SIZE != null && !myConfiguration.HEAP_SIZE.trim().isEmpty()) {
         String param = JavaSdkUtil.isJdkAtLeast(jdk, JavaSdkVersion.JDK_1_2) ? "-J-Xmx" : "-J-mx";
         cmdLine.getParametersList().prepend(param + myConfiguration.HEAP_SIZE + "m");
       }
@@ -155,7 +155,7 @@ public final class JavadocGeneratorRunProfile implements ModuleRunProfile {
     private void setParameters(Sdk jdk, GeneralCommandLine cmdLine) throws CantRunException {
       ParametersList parameters = cmdLine.getParametersList();
 
-      if (myConfiguration.LOCALE != null && myConfiguration.LOCALE.length() > 0) {
+      if (myConfiguration.LOCALE != null && !myConfiguration.LOCALE.isEmpty()) {
         parameters.add("-locale");
         parameters.add(myConfiguration.LOCALE);
       }

java/java-impl/src/com/intellij/lang/java/JavaDocumentationProvider.java

@@ -180,7 +180,7 @@ public class JavaDocumentationProvider implements CodeDocumentationProvider, Ext
 
     if (file instanceof PsiJavaFile) {
       String packageName = ((PsiJavaFile)file).getPackageName();
-      if (packageName.length() > 0) {
+      if (!packageName.isEmpty()) {
         buffer.append(packageName);
         newLine(buffer);
       }
@@ -649,7 +649,7 @@ public class JavaDocumentationProvider implements CodeDocumentationProvider, Ext
         createTypeParamsListComment(builder, commenter, typeParameterList);
       }
     }
-    return builder.length() > 0 ? builder.toString() : null;
+    return !builder.isEmpty() ? builder.toString() : null;
   }
 
   public static void generateParametersTakingDocFromSuperMethods(StringBuilder builder,

java/java-impl/src/com/intellij/packageDependencies/ui/PackageNode.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.packageDependencies.ui;
 
 import com.intellij.cyclicDependencies.ui.CyclicDependenciesPanel;
@@ -26,11 +26,11 @@ public class PackageNode extends PackageDependenciesNode {
     super(aPackage.getProject());
     myPackage = aPackage;
     myPackageName = showFQName ? aPackage.getQualifiedName() : aPackage.getName();
-    if (myPackageName == null || myPackageName.length() == 0) {
+    if (myPackageName == null || myPackageName.isEmpty()) {
       myPackageName = CyclicDependenciesPanel.getDefaultPackageAbbreviation();
     }
     String packageQName = aPackage.getQualifiedName();
-    if (packageQName.length() == 0) {
+    if (packageQName.isEmpty()) {
       packageQName = null;
     }
     myPackageQName = packageQName;

java/java-impl/src/com/intellij/psi/codeStyle/JavaPackageEntryTableAccessor.java

@@ -26,7 +26,7 @@ public class JavaPackageEntryTableAccessor extends ValueListPropertyAccessor<Pac
     PackageEntryTable entryTable = new PackageEntryTable();
     for (String strValue : strList) {
       String parseStr = strValue.trim();
-      if (parseStr.length() > 0 && parseStr.charAt(0) == BLANK_LINE_CHAR) {
+      if (!parseStr.isEmpty() && parseStr.charAt(0) == BLANK_LINE_CHAR) {
         for (int i = 0; i < parseStr.length(); i ++) {
           if (parseStr.charAt(i) == BLANK_LINE_CHAR) {
             entryTable.addEntry(PackageEntry.BLANK_LINE_ENTRY);

java/java-impl/src/com/intellij/psi/codeStyle/arrangement/JavaRearranger.java

@@ -29,8 +29,8 @@ import org.jetbrains.annotations.Nullable;
 import org.jetbrains.annotations.Unmodifiable;
 
 import java.awt.*;
-import java.util.List;
 import java.util.*;
+import java.util.List;
 
 import static com.intellij.psi.codeStyle.arrangement.std.StdArrangementTokens.EntryType.*;
 import static com.intellij.psi.codeStyle.arrangement.std.StdArrangementTokens.General.*;
@@ -273,7 +273,7 @@ public final class JavaRearranger implements Rearranger<JavaElementArrangementEn
       for (ArrangementEntryDependencyInfo fieldInInitializerInfo : root.getDependentEntriesInfos()) {
         JavaElementArrangementEntry fieldInInitializer = fieldInInitializerInfo.getAnchorEntry();
         if (arrangedFields.indexOf(fieldInInitializer) > anchorEntryIndex ||
-            fieldInInitializerInfo.getDependentEntriesInfos().size() > 0) {
+            !fieldInInitializerInfo.getDependentEntriesInfos().isEmpty()) {
           anchorField.addDependency(fieldInInitializer);
         }
       }

java/java-impl/src/com/intellij/psi/formatter/java/AbstractJavaBlock.java

@@ -874,7 +874,7 @@ public abstract class AbstractJavaBlock extends AbstractBlock implements JavaBlo
       // hence, no alignment should be applied to them in order to avoid subsequent blocks aligned with the same alignment to
       // be located at the left editor edge as well.
       CharSequence prevChars;
-      if (previous != null && previous.getElementType() == TokenType.WHITE_SPACE && (prevChars = previous.getChars()).length() > 0
+      if (previous != null && previous.getElementType() == TokenType.WHITE_SPACE && !(prevChars = previous.getChars()).isEmpty()
           && prevChars.charAt(prevChars.length() - 1) == '\n') {
         return false;
       }

java/java-impl/src/com/intellij/psi/formatter/java/ChainMethodCallsBlockBuilder.java

@@ -222,7 +222,7 @@ class ChainMethodCallsBlockBuilder {
     }
 
     private @Nullable String getIndentString() {
-      if (nodes.size() > 0) {
+      if (!nodes.isEmpty()) {
         ASTNode prev = nodes.get(0).getTreePrev();
         if (prev != null && prev.getPsi() instanceof PsiWhiteSpace && prev.textContains('\n')) {
           CharSequence whitespace = prev.getChars();

java/java-impl/src/com/intellij/psi/impl/source/codeStyle/javadoc/JDComment.java

@@ -125,7 +125,7 @@ public class JDComment {
         sb.delete(nlen, sb.length());
       }
     }
-    else if (sb.length() == 0 && !StringUtil.isEmpty(myEndLine)) {
+    else if (sb.isEmpty() && !StringUtil.isEmpty(myEndLine)) {
       sb.append(prefix).append('\n');
     }
 

java/java-impl/src/com/intellij/psi/impl/source/codeStyle/javadoc/JDParser.java

@@ -255,14 +255,14 @@ public class JDParser {
           }
         }
         else {
-          if (sb.length() > 0) {
+          if (!sb.isEmpty()) {
             sb.append('\n');
           }
           sb.append(line);
         }
       }
       else {
-        if (sb.length() > 0) {
+        if (!sb.isEmpty()) {
           sb.append('\n');
         }
       }
@@ -606,7 +606,7 @@ public class JDParser {
             endParagraph(result, sb);
           }
 
-          if (sb.length() != 0) sb.append(' ');
+          if (!sb.isEmpty()) sb.append(' ');
           if (markdownComment && !sb.isEmpty()) {
             // When fusing lines together, horizontal spacing loses its meaning
             sb.append(s1.trim());
@@ -617,7 +617,7 @@ public class JDParser {
         }
       }
     }
-    if (!mySettings.JD_PRESERVE_LINE_FEEDS && sb.length() != 0) {
+    if (!mySettings.JD_PRESERVE_LINE_FEEDS && !sb.isEmpty()) {
       result.add(new Pair<>(sb.toString(), false));
     }
     return result;
@@ -656,7 +656,7 @@ public class JDParser {
   }
 
   private static void endParagraph(@NotNull List<? super Pair<String, Boolean>> result, @NotNull StringBuilder sb) {
-    if (sb.length() > 0) {
+    if (!sb.isEmpty()) {
       result.add(new Pair<>(sb.toString(), false));
       sb.setLength(0);
     }

java/java-impl/src/com/intellij/psi/impl/source/tree/injected/MyTestInjector.java

@@ -244,7 +244,7 @@ public class MyTestInjector {
           if (!method.hasModifierProperty(PsiModifier.NATIVE) || !method.hasModifierProperty(PsiModifier.PUBLIC)) return;
           StringBuilder paramList = new StringBuilder();
           for (PsiParameter parameter : method.getParameterList().getParameters()) {
-            if (paramList.length() > 0) paramList.append(",");
+            if (!paramList.isEmpty()) paramList.append(",");
             paramList.append(parameter.getName());
           }
           @NonNls String header = "function " + method.getName() + "("+paramList+") {";

java/java-impl/src/com/intellij/psi/search/scope/packageSet/PatternPackageSetParserExtension.java

@@ -1,4 +1,4 @@
-// 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.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 
 package com.intellij.psi.search.scope.packageSet;
 
@@ -72,7 +72,7 @@ public final class PatternPackageSetParserExtension implements PackageSetParserE
       lexer.advance();
     }
 
-    if (pattern.length() == 0) {
+    if (pattern.isEmpty()) {
       error(CodeInsightBundle.message("error.package.set.pattern.expectations"), lexer);
     }
 

java/java-impl/src/com/intellij/testIntegration/createTest/CreateTestDialog.java

@@ -52,8 +52,8 @@ import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
 import java.awt.event.InputEvent;
 import java.awt.event.KeyEvent;
-import java.util.List;
 import java.util.*;
+import java.util.List;
 
 import static com.intellij.testIntegration.createTest.CreateTestUtils.selectTargetDirectory;
 
@@ -449,7 +449,7 @@ public class CreateTestDialog extends DialogWrapper {
 
   public @Nullable String getSuperClassName() {
     String result = mySuperClassField.getText().trim();
-    if (result.length() == 0) return null;
+    if (result.isEmpty()) return null;
     return result;
   }
 

java/java-impl/src/com/intellij/ui/ReferenceEditorComboWithBrowseButton.java

@@ -31,7 +31,7 @@ public class ReferenceEditorComboWithBrowseButton extends ComponentWithBrowseBut
     if (recentEntries != null) {
       setHistory(ArrayUtilRt.toStringArray(recentEntries));
     }
-    if (text != null && text.length() > 0) {
+    if (text != null && !text.isEmpty()) {
       prependItem(text);
     }
     else if (text != null) {

java/java-impl/src/com/intellij/util/text/ElementPresentation.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2009 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.util.text;
 
 import com.intellij.core.JavaPsiBundle;
@@ -67,7 +53,7 @@ public abstract class ElementPresentation {
   public String getNameWithFQComment() {
     String comment = getComment();
     String result = getName();
-    if (comment.trim().length() == 0) return result;
+    if (comment.trim().isEmpty()) return result;
     return result + " (" + comment + ")";
   }
 
@@ -180,7 +166,7 @@ public abstract class ElementPresentation {
     @Override
     public @NlsSafe String getQualifiedName() {
       String qualifiedName = myPsiPackage.getQualifiedName();
-      if (qualifiedName.length() == 0) return JavaBundle.message("default.package.presentable.name");
+      if (qualifiedName.isEmpty()) return JavaBundle.message("default.package.presentable.name");
       return qualifiedName;
     }
 

java/java-impl/src/com/intellij/util/xml/impl/ExtendsClassChecker.java

@@ -83,7 +83,7 @@ public final class ExtendsClassChecker extends DomCustomAnnotationChecker<Extend
         .collect(Collectors.toSet());
 
     final SmartList<DomElementProblemDescriptor> list = new SmartList<>();
-    if (toExtend.size() > 0) {
+    if (!toExtend.isEmpty()) {
       if (!Arrays.asList(names).contains(value.getQualifiedName())
           && ContainerUtil.find(toExtend, aClass -> value.isInheritor(aClass, true)) == null) {
         String message = JavaBundle.message("class.is.not.a.subclass", value.getQualifiedName(), StringUtil.join(names, ","));

java/java-impl/src/com/siyeh/ig/errorhandling/ThrowableSupplierOnlyThrowExceptionInspection.java

@@ -152,7 +152,7 @@ public final class ThrowableSupplierOnlyThrowExceptionInspection extends BaseIns
       }
 
       List<PsiThrowStatement> all = getThrowStatements(lambdaSupplier);
-      if (all.size() == 0) {
+      if (all.isEmpty()) {
         return;
       }
       PsiIdentifier[] identifiers = PsiTreeUtil.getChildrenOfType(expression.getMethodExpression(), PsiIdentifier.class);

java/java-impl/src/com/siyeh/ipp/concatenation/ReplaceFormatStringWithConcatenationIntention.java

@@ -100,17 +100,17 @@ public final class ReplaceFormatStringWithConcatenationIntention extends MCInten
     int count = 0;
     while (end >= 0) {
       if (end > start) {
-        if (builder.length() > 0) {
+        if (!builder.isEmpty()) {
           builder.append('+');
         }
         builder.append('"').append(StringUtil.escapeStringCharacters(value.substring(start, end))).append('"');
       }
-      if (builder.length() > 0) {
+      if (!builder.isEmpty()) {
         builder.append('+');
       }
       count++;
       final PsiExpression argument = arguments[indexOfFormatString + count];
-      if (builder.length() == 0 && !ExpressionUtils.hasStringType(argument)) {
+      if (builder.isEmpty() && !ExpressionUtils.hasStringType(argument)) {
         builder.append("String.valueOf(").append(commentTracker.text(argument)).append(')');
       }
       else {
@@ -120,7 +120,7 @@ public final class ReplaceFormatStringWithConcatenationIntention extends MCInten
       end = value.indexOf("%s", start);
     }
     if (start < value.length()) {
-      if (builder.length() > 0) {
+      if (!builder.isEmpty()) {
         builder.append('+');
       }
       builder.append('"').append(StringUtil.escapeStringCharacters(value.substring(start))).append('"');

java/java-impl/src/com/siyeh/ipp/constant/ConstantSubexpressionIntention.java

@@ -90,7 +90,7 @@ public final class ConstantSubexpressionIntention extends MCIntention {
         newExpressionText.append(prevToken.getText());
       }
       if (token == currentToken) {
-        if (newExpressionText.length() > 0) {
+        if (!newExpressionText.isEmpty()) {
           newExpressionText.append(' ');
         }
         if (value instanceof Long) {

java/java-psi-impl/src/com/intellij/codeInsight/folding/impl/CommentFoldingUtil.java

@@ -210,7 +210,7 @@ public final class CommentFoldingUtil {
     final StringBuilder sb = new StringBuilder();
     sb.append(prefix);
 
-    if (text != null && text.length() > 0) {
+    if (text != null && !text.isEmpty()) {
       sb.append(text);
       sb.append(" ");
     }

java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/InferenceVariablesOrder.java

@@ -164,7 +164,7 @@ public final class InferenceVariablesOrder {
       boolean includeSelfDependency = false;
       for (Iterator<InferenceGraphNode<T>> iterator = myDependencies.iterator(); iterator.hasNext(); ) {
         InferenceGraphNode<T> d = iterator.next();
-        assert d.myValue.size() >= 1;
+        assert !d.myValue.isEmpty();
         final T initialNodeValue = d.myValue.get(0);
         if (myValue.contains(initialNodeValue)) {
           includeSelfDependency = true;

java/java-psi-impl/src/com/intellij/util/text/LiteralFormatUtil.java

@@ -32,7 +32,7 @@ public final class LiteralFormatUtil {
       groupSize = 4;  // hex, bin
     }
 
-    if (text.length() == 0) return original;
+    if (text.isEmpty()) return original;
 
     final char last = text.charAt(text.length() - 1);
     if (StringUtil.containsChar("Ll", last) ||
@@ -42,7 +42,7 @@ public final class LiteralFormatUtil {
       text = text.substring(0, pos);
     }
 
-    if (text.length() == 0) return original;
+    if (text.isEmpty()) return original;
 
     boolean hasPoint = false;
     String fractional = "";

java/java-runtime/src/com/intellij/rt/ant/execution/IdeaInputHandler.java

@@ -1,4 +1,4 @@
-// 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.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.rt.ant.execution;
 
 import org.apache.tools.ant.BuildException;
@@ -26,7 +26,7 @@ public class IdeaInputHandler implements InputHandler {
     if (request instanceof MultipleChoiceInputRequest) {
       @SuppressWarnings("unchecked") 
       List<String> choices = ((MultipleChoiceInputRequest)request).getChoices();
-      if (choices != null && choices.size() > 0) {
+      if (choices != null && !choices.isEmpty()) {
         int count = choices.size();
         packet.appendLong(count);
         for (String choice : choices) {

java/java-runtime/src/com/intellij/rt/execution/testFrameworks/ForkedByModuleSplitter.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2015 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.rt.execution.testFrameworks;
 
 import java.io.*;
@@ -83,7 +69,7 @@ public abstract class ForkedByModuleSplitter {
     }
 
     builder.add("-classpath");
-    if (myDynamicClasspath.length() > 0) {
+    if (!myDynamicClasspath.isEmpty()) {
       try {
         if ("ARGS_FILE".equals(myDynamicClasspath)) {
           File argFile = File.createTempFile("arg_file", null);
@@ -154,7 +140,7 @@ public abstract class ForkedByModuleSplitter {
         final String classpath = perDirReader.readLine();
         List<String> moduleOptions = new ArrayList<>();
         String modulePath = perDirReader.readLine();
-        if (modulePath != null && modulePath.length() > 0) {
+        if (modulePath != null && !modulePath.isEmpty()) {
           moduleOptions.add("-p");
           moduleOptions.add(modulePath);
         }

java/java-runtime/src/com/intellij/rt/execution/testFrameworks/ForkedSplitter.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.rt.execution.testFrameworks;
 
 import com.intellij.rt.execution.junit.RepeatCount;
@@ -30,7 +30,7 @@ public abstract class ForkedSplitter<T> extends ForkedByModuleSplitter {
       final String classpath = System.getProperty("java.class.path");
       final String modulePath = System.getProperty("jdk.module.path");
       final List<String> moduleOptions = new ArrayList<>();
-      if (modulePath != null && modulePath.length() > 0) {
+      if (modulePath != null && !modulePath.isEmpty()) {
         moduleOptions.add("-p");
         moduleOptions.add(modulePath);
       }

java/java-runtime/src/com/intellij/rt/execution/testFrameworks/ProcessBuilder.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.rt.execution.testFrameworks;
 
 import java.io.File;
@@ -67,7 +53,7 @@ public class ProcessBuilder {
   //
   // If either of these becomes an issue, please refer to [util] CommandLineUtil.addToWindowsCommandLine() for a possible implementation.
   public Process createProcess() throws IOException {
-    if (myParameters.size() < 1) {
+    if (myParameters.isEmpty()) {
       throw new IllegalArgumentException("Executable name not specified");
     }
 
@@ -91,7 +77,7 @@ public class ProcessBuilder {
           while ((pos = parameter.indexOf('\"', pos)) >= 0);
           parameter = buffer.toString();
         }
-        else if (parameter.length() == 0) {
+        else if (parameter.isEmpty()) {
           parameter = "\"\"";
         }
 

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

@@ -351,7 +351,7 @@ public final class JavaStructuralSearchProfile extends StructuralSearchProfile {
   }
 
   private static boolean shouldTryExpressionPattern(@NotNull List<? extends PsiElement> elements) {
-    if (elements.size() >= 1 && elements.size() <= 3) {
+    if (!elements.isEmpty() && elements.size() <= 3) {
       final PsiElement firstElement = elements.get(0);
       if (firstElement instanceof PsiDeclarationStatement) {
         final PsiElement lastChild = firstElement.getLastChild();

java/testFramework/src/com/intellij/debugger/BreakpointComment.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.debugger;
 
 import com.intellij.openapi.util.Pair;
@@ -144,7 +144,7 @@ public final class BreakpointComment {
   public void done() {
     if (kind != null) throw error("Unprocessed kind '" + kind + "'");
     if (kindValue != null) throw error("Unprocessed kind value '" + kindValue + "'");
-    if (values.size() >= 1) {
+    if (!values.isEmpty()) {
       String valid = String.join(", ", validValues);
       String msg = "Unprocessed %s '%s', %s".formatted(
         values.size() > 1 ? "values" : "value",

java/typeMigration/src/com/intellij/refactoring/typeMigration/TypeConversionDescriptor.java

@@ -110,11 +110,11 @@ public class TypeConversionDescriptor extends TypeConversionDescriptorBase {
       buf.append(myReplaceByString);
     }
     if (myStringToReplace != null) {
-      if (buf.length() > 0) buf.append(" ");
+      if (!buf.isEmpty()) buf.append(" ");
       buf.append(myStringToReplace);
     }
     if (myExpression != null) {
-      if (buf.length() > 0) buf.append(" ");
+      if (!buf.isEmpty()) buf.append(" ");
       buf.append(myExpression.getText());
     }
     return buf.toString();

java/unscramble/src/com/intellij/unscramble/UnscrambleUtils.java

@@ -111,7 +111,7 @@ public final class UnscrambleUtils {
     int linesCount = 0;
     for (String line : text.split("\n")) {
       line = line.trim();
-      if (line.length() == 0) continue;
+      if (line.isEmpty()) continue;
       line = StringUtil.trimEnd(line, "\r");
       if (STACKTRACE_LINE.matcher(line).matches()) {
         linesCount++;

jps/antLayout/src/jetbrains/antlayout/datatypes/ExtractedDirContent.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2012 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package jetbrains.antlayout.datatypes;
 
 import jetbrains.antlayout.util.LayoutFileSet;
@@ -56,7 +42,7 @@ public class ExtractedDirContent extends Content {
     if (pathInJar.startsWith("/")) {
       pathInJar = pathInJar.substring(1);
     }
-    if (pathInJar.length() > 0) {
+    if (!pathInJar.isEmpty()) {
       final PatternSet patternSet = new PatternSet();
       patternSet.createInclude().setName(pathInJar + "**");
       expandTask.addPatternset(patternSet);

jps/antLayout/src/jetbrains/antlayout/datatypes/RootContainer.java

@@ -1,4 +1,4 @@
-// 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.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package jetbrains.antlayout.datatypes;
 
 import jetbrains.antlayout.util.LayoutFileSet;
@@ -32,7 +32,7 @@ public class RootContainer extends Container {
         task.setTaskName("copy");
         task.setProject(getProject());
         String prefix = set.getPrefix(getProject());
-        File target = prefix.length() > 0 ? new File(destDirectory, prefix + "/") : destDirectory;
+        File target = !prefix.isEmpty() ? new File(destDirectory, prefix + "/") : destDirectory;
 
         target.mkdirs();
 

jps/jps-builders-6/src/org/jetbrains/jps/javac/InputFileObject.java

@@ -61,7 +61,7 @@ final class InputFileObject extends JpsFileObject {
     final String fPath = myFile.getPath();
     for (File dir: path) {
       String dirPath = dir.getPath();
-      if (dirPath.length() == 0) {
+      if (dirPath.isEmpty()) {
         dirPath = System.getProperty("user.dir");
       }
       if (!fPath.regionMatches(!caseSensitiveFS, 0, dirPath, 0, dirPath.length())) {