platform/lang-api/src/com/intellij/psi/PsiRecursiveElementWalkingVisitor.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.psi;
  17
  18 import com.intellij.openapi.progress.ProgressManager;
  19 import org.jetbrains.annotations.NotNull;
  20
  21 import java.util.List;
  22
  23 /**
  24  * Represents a PSI element visitor which recursively visits the children of the element
  25  * on which the visit was started.
  26  */
  27 public abstract class PsiRecursiveElementWalkingVisitor extends PsiElementVisitor  {
  28   private final boolean myVisitAllFileRoots;
  29   private final PsiWalkingState myWalkingState = new PsiWalkingState(this){
  30     public void elementFinished(@NotNull PsiElement element) {
  31       PsiRecursiveElementWalkingVisitor.this.elementFinished(element);
  32     }
  33   };
  34
  35   protected PsiRecursiveElementWalkingVisitor() {
  36     this(false);
  37   }
  38
  39   protected PsiRecursiveElementWalkingVisitor(boolean visitAllFileRoots) {
  40     myVisitAllFileRoots = visitAllFileRoots;
  41   }
  42
  43   public void visitElement(final PsiElement element) {
  44     ProgressManager.checkCanceled();
  45
  46     myWalkingState.elementStarted(element);
  47   }
  48
  49   protected void elementFinished(PsiElement element) {
  50
  51   }
  52
  53   @Override
  54   public void visitFile(final PsiFile file) {
  55     if (myVisitAllFileRoots) {
  56       final FileViewProvider viewProvider = file.getViewProvider();
  57       final List<PsiFile> allFiles = viewProvider.getAllFiles();
  58       if (allFiles.size() > 1) {
  59         if (file == viewProvider.getPsi(viewProvider.getBaseLanguage())) {
  60           for (PsiFile lFile : allFiles) {
  61             lFile.acceptChildren(this);
  62           }
  63           return;
  64         }
  65       }
  66     }
  67
  68     super.visitFile(file);
  69   }
  70 }