diff --git a/java/java-impl/src/com/intellij/psi/impl/source/resolve/PsiResolveHelperImpl.java b/java/java-impl/src/com/intellij/psi/impl/source/resolve/PsiResolveHelperImpl.java
index 3b6b01ab4877..25d1e4888517 100644
--- a/java/java-impl/src/com/intellij/psi/impl/source/resolve/PsiResolveHelperImpl.java
+++ b/java/java-impl/src/com/intellij/psi/impl/source/resolve/PsiResolveHelperImpl.java
@@ -722,7 +722,7 @@ public class PsiResolveHelperImpl implements PsiResolveHelper {
   }
 
   @Nullable
-  private static Pair<PsiType, ConstraintType> inferTypeForCompletionFromCallContext(final PsiCallExpression innerMethodCall,
+  private static Pair<PsiType, ConstraintType> inferTypeForCompletionFromCallContext(@NotNull final PsiCallExpression innerMethodCall,
                                                                                      final PsiExpressionList expressionList,
                                                                                      final PsiCallExpression contextCall,
                                                                                      final PsiTypeParameter typeParameter) {
diff --git a/platform/util/src/com/intellij/openapi/util/RecursionGuard.java b/platform/util/src/com/intellij/openapi/util/RecursionGuard.java
index 43f3c881b38e..b0843e3e32eb 100644
--- a/platform/util/src/com/intellij/openapi/util/RecursionGuard.java
+++ b/platform/util/src/com/intellij/openapi/util/RecursionGuard.java
@@ -15,6 +15,7 @@
  */
 package com.intellij.openapi.util;
 
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
@@ -32,7 +33,7 @@ public abstract class RecursionGuard {
   @SuppressWarnings("JavaDoc")
   @Deprecated
   @Nullable
-  public <T> T doPreventingRecursion(Object key, Computable<T> computation) {
+  public <T> T doPreventingRecursion(@NotNull Object key, Computable<T> computation) {
     return doPreventingRecursion(key, false, computation);
   }
 
@@ -45,7 +46,7 @@ public abstract class RecursionGuard {
    * @return the result of the computation or null if we're entering a computation with this key on this thread recursively,
    */
   @Nullable
-  public abstract <T> T doPreventingRecursion(Object key, boolean memoize, Computable<T> computation);
+  public abstract <T> T doPreventingRecursion(@NotNull Object key, boolean memoize, Computable<T> computation);
 
   /**
    * Used in pair with {@link com.intellij.openapi.util.RecursionGuard.StackStamp#mayCacheNow()} to ensure that cached are only the reliable values,
diff --git a/platform/util/src/com/intellij/openapi/util/RecursionManager.java b/platform/util/src/com/intellij/openapi/util/RecursionManager.java
index bb3917831278..f03e33ef71e5 100644
--- a/platform/util/src/com/intellij/openapi/util/RecursionManager.java
+++ b/platform/util/src/com/intellij/openapi/util/RecursionManager.java
@@ -18,6 +18,7 @@ package com.intellij.openapi.util;
 import com.intellij.reference.SoftReference;
 import com.intellij.util.containers.SoftHashMap;
 import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
@@ -78,7 +79,7 @@ public class RecursionManager {
   public static RecursionGuard createGuard(@NonNls final String id) {
     return new RecursionGuard() {
       @Override
-      public <T> T doPreventingRecursion(Object key, boolean memoize, Computable<T> computation) {
+      public <T> T doPreventingRecursion(@NotNull Object key, boolean memoize, Computable<T> computation) {
         MyKey realKey = new MyKey(id, key);
         LinkedHashMap<MyKey, Integer> progressMap = ourProgress.get();
         if (progressMap.containsKey(realKey)) {
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/GroovyPsiManager.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/GroovyPsiManager.java
index bc7e4ecc97e4..f012fa1a6223 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/GroovyPsiManager.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/GroovyPsiManager.java
@@ -183,7 +183,7 @@ public class GroovyPsiManager {
   }
 
   @Nullable
-  public static PsiType inferType(PsiElement element, Computable<PsiType> computable) {
+  public static PsiType inferType(@NotNull PsiElement element, Computable<PsiType> computable) {
     List<Object> stack = ourGuard.currentStack();
     if (stack.size() > 7) { //don't end up walking the whole project PSI
       ourGuard.prohibitResultCaching(stack.get(0));
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/TypeInferenceHelper.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/TypeInferenceHelper.java
index 93f284a57906..e053645d7297 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/TypeInferenceHelper.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/TypeInferenceHelper.java
@@ -23,6 +23,7 @@ import com.intellij.psi.PsiType;
 import com.intellij.psi.util.*;
 import gnu.trove.TIntHashSet;
 import gnu.trove.TIntObjectHashMap;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.plugins.groovy.lang.lexer.TokenSets;
 import org.jetbrains.plugins.groovy.lang.psi.GrControlFlowOwner;
@@ -52,7 +53,7 @@ import java.util.List;
 public class TypeInferenceHelper {
 
   @Nullable
-  public static PsiType getInferredType(final GrReferenceExpression refExpr) {
+  public static PsiType getInferredType(@NotNull final GrReferenceExpression refExpr) {
     return RecursionManager.createGuard("refType").doPreventingRecursion(refExpr, true, new Computable<PsiType>() {
       @Override
       public PsiType compute() {
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java
index 440b886b1d50..4c578284f6b9 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java
@@ -128,7 +128,7 @@ public class GrClassImplUtil {
   }
 
   @Nullable
-  private static List<PsiClassType> getImplementsFromDelegate(final GrTypeDefinition grType, final Set<PsiClass> visited) {
+  private static List<PsiClassType> getImplementsFromDelegate(@NotNull final GrTypeDefinition grType, final Set<PsiClass> visited) {
     return RecursionManager.createGuard("groovyDelegateFields").doPreventingRecursion(grType, true, new Computable<List<PsiClassType>>() {
       @Override
       public List<PsiClassType> compute() {
diff --git a/xml/impl/src/com/intellij/xml/util/XmlUtil.java b/xml/impl/src/com/intellij/xml/util/XmlUtil.java
index b9d602d506f7..e1aaa783b9b2 100644
--- a/xml/impl/src/com/intellij/xml/util/XmlUtil.java
+++ b/xml/impl/src/com/intellij/xml/util/XmlUtil.java
@@ -667,7 +667,7 @@ public class XmlUtil {
       return true;
     }
 
-    private boolean processXInclude(final boolean deepFlag, final boolean wideFlag, final XmlTag xincludeTag) {
+    private boolean processXInclude(final boolean deepFlag, final boolean wideFlag, @NotNull final XmlTag xincludeTag) {
 
       final PsiElement[] inclusion = CachedValuesManager.getManager(xincludeTag.getProject()).getCachedValue(xincludeTag, new CachedValueProvider<PsiElement[]>() {
           public Result<PsiElement[]> compute() {