diff --git a/java/java-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/JavaClassReference.java b/java/java-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/JavaClassReference.java
index 63d6048183ae..e73e5c627192 100644
--- a/java/java-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/JavaClassReference.java
+++ b/java/java-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/JavaClassReference.java
@@ -180,12 +180,9 @@ public class JavaClassReference extends GenericReference implements PsiJavaRefer
   @Override
   public PsiElement handleElementRename(String newElementName) throws IncorrectOperationException {
     final ElementManipulator<PsiElement> manipulator = getManipulator(getElement());
-    if (manipulator != null) {
-      final PsiElement element = manipulator.handleContentChange(getElement(), getRangeInElement(), newElementName);
-      myRange = new TextRange(getRangeInElement().getStartOffset(), getRangeInElement().getStartOffset() + newElementName.length());
-      return element;
-    }
-    throw new IncorrectOperationException("Manipulator for this element is not defined: " + getElement());
+    final PsiElement element = manipulator.handleContentChange(getElement(), getRangeInElement(), newElementName);
+    myRange = new TextRange(getRangeInElement().getStartOffset(), getRangeInElement().getStartOffset() + newElementName.length());
+    return element;
   }
 
   @Override
@@ -215,12 +212,9 @@ public class JavaClassReference extends GenericReference implements PsiJavaRefer
     }
     TextRange range = new TextRange(myJavaClassReferenceSet.getReference(0).getRangeInElement().getStartOffset(), end);
     final ElementManipulator<PsiElement> manipulator = getManipulator(getElement());
-    if (manipulator != null) {
-      final PsiElement finalElement = manipulator.handleContentChange(getElement(), range, newName);
-      myJavaClassReferenceSet.reparse(finalElement, TextRange.from(range.getStartOffset(), newName.length()));
-      return finalElement;
-    }
-    return element;
+    final PsiElement finalElement = manipulator.handleContentChange(getElement(), range, newName);
+    myJavaClassReferenceSet.reparse(finalElement, TextRange.from(range.getStartOffset(), newName.length()));
+    return finalElement;
   }
 
   @Override
diff --git a/platform/core-api/src/com/intellij/psi/PsiElement.java b/platform/core-api/src/com/intellij/psi/PsiElement.java
index 9f1b0d026376..e6394bb13b1c 100644
--- a/platform/core-api/src/com/intellij/psi/PsiElement.java
+++ b/platform/core-api/src/com/intellij/psi/PsiElement.java
@@ -96,7 +96,6 @@ public interface PsiElement extends UserDataHolder, Iconable {
    *
    * @return the first child, or null if the element has no children.
    */
-  @Nullable
   PsiElement getFirstChild();
 
   /**
@@ -104,7 +103,6 @@ public interface PsiElement extends UserDataHolder, Iconable {
    *
    * @return the last child, or null if the element has no children.
    */
-  @Nullable
   PsiElement getLastChild();
 
   /**
diff --git a/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/CachingReference.java b/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/CachingReference.java
index fe032d918805..5f59d511a03b 100644
--- a/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/CachingReference.java
+++ b/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/CachingReference.java
@@ -21,6 +21,7 @@ import com.intellij.psi.ElementManipulators;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiReference;
 import com.intellij.psi.impl.source.resolve.ResolveCache;
+import com.intellij.util.IncorrectOperationException;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -46,9 +47,13 @@ public abstract class CachingReference implements PsiReference, EmptyResolveMess
     return false;
   }
 
-  @Nullable
+  @NotNull
   public static <T extends PsiElement> ElementManipulator<T> getManipulator(T currentElement){
-    return ElementManipulators.getManipulator(currentElement);
+    ElementManipulator<T> manipulator = ElementManipulators.getManipulator(currentElement);
+    if (manipulator == null) {
+      throw new IncorrectOperationException("Manipulator for this element is not defined: " + currentElement);
+    }
+    return manipulator;
   }
 
   private static class MyResolver implements ResolveCache.Resolver {
diff --git a/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/FileReference.java b/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/FileReference.java
index 2f37c1431a18..ae652a95a1e0 100644
--- a/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/FileReference.java
+++ b/platform/lang-impl/src/com/intellij/psi/impl/source/resolve/reference/impl/providers/FileReference.java
@@ -399,18 +399,15 @@ public class FileReference implements FileReferenceOwner, PsiPolyVariantReferenc
   @Override
   public PsiElement handleElementRename(String newElementName) throws IncorrectOperationException {
     final ElementManipulator<PsiElement> manipulator = CachingReference.getManipulator(getElement());
-    if (manipulator != null) {
-      myFileReferenceSet.setElement(manipulator.handleContentChange(getElement(), getRangeInElement(), newElementName));
-      //Correct ranges
-      int delta = newElementName.length() - myRange.getLength();
-      myRange = new TextRange(getRangeInElement().getStartOffset(), getRangeInElement().getStartOffset() + newElementName.length());
-      FileReference[] references = myFileReferenceSet.getAllReferences();
-      for (int idx = myIndex + 1; idx < references.length; idx++) {
-        references[idx].myRange = references[idx].myRange.shiftRight(delta);
-      }
-      return myFileReferenceSet.getElement();
+    myFileReferenceSet.setElement(manipulator.handleContentChange(getElement(), getRangeInElement(), newElementName));
+    //Correct ranges
+    int delta = newElementName.length() - myRange.getLength();
+    myRange = new TextRange(getRangeInElement().getStartOffset(), getRangeInElement().getStartOffset() + newElementName.length());
+    FileReference[] references = myFileReferenceSet.getAllReferences();
+    for (int idx = myIndex + 1; idx < references.length; idx++) {
+      references[idx].myRange = references[idx].myRange.shiftRight(delta);
     }
-    throw new IncorrectOperationException("Manipulator for this element is not defined: " + getElement());
+    return myFileReferenceSet.getElement();
   }
 
   public PsiElement bindToElement(@NotNull final PsiElement element, final boolean absolute) throws IncorrectOperationException {