add method to PsiTreeUtil

java/java-impl/src/com/intellij/codeInsight/editorActions/moveLeftRight/JavaMoveLeftRightHandler.java

@@ -63,13 +63,8 @@ public class JavaMoveLeftRightHandler extends MoveElementLeftRightHandler {
       return ((PsiTypeParameterList)element).getTypeParameters();
     }
     else if (element instanceof PsiModifierList) {
-      final List<PsiElement> result = ContainerUtil.newSmartList();
-      for (PsiElement child = element.getFirstChild(); child != null; child = child.getNextSibling()) {
-        if (child instanceof PsiKeyword || child instanceof PsiAnnotation) {
-          result.add(child);
-        }
-      }
-      return result.toArray(PsiElement.EMPTY_ARRAY);
+      final List<PsiElement> elements = PsiTreeUtil.getChildrenOfAnyType(element, PsiKeyword.class, PsiAnnotation.class);
+      return elements.toArray(PsiElement.EMPTY_ARRAY);
     }
     return PsiElement.EMPTY_ARRAY;
   }

platform/core-api/src/com/intellij/psi/util/PsiTreeUtil.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2015 JetBrains s.r.o.
+ * 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.
@@ -346,6 +346,21 @@ public class PsiTreeUtil {
     return result == null ? null : ArrayUtil.toObjectArray(result, aClass);
   }
 
+  @Nullable
+  public static <T extends PsiElement> List<T> getChildrenOfAnyType(@Nullable PsiElement element, @NotNull Class<? extends T>... classes) {
+    if (element == null) return ContainerUtil.emptyList();
+
+    List<T> result = null;
+    for (PsiElement child = element.getFirstChild(); child != null; child = child.getNextSibling()) {
+      if (instanceOf(child, classes)) {
+        if (result == null) result = ContainerUtil.newSmartList();
+        //noinspection unchecked
+        result.add((T)child);
+      }
+    }
+    return result;
+  }
+
   @NotNull
   public static <T extends PsiElement> List<T> getChildrenOfTypeAsList(@Nullable PsiElement element, @NotNull Class<T> aClass) {
     if (element == null) return Collections.emptyList();