plugins/InspectionGadgets/src/com/siyeh/ig/psiutils/VariableUsedVisitor.java

   1 /*
   2  * Copyright 2003-2005 Dave Griffith
   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.siyeh.ig.psiutils;
  17
  18 import com.intellij.psi.JavaRecursiveElementVisitor;
  19 import com.intellij.psi.PsiElement;
  20 import com.intellij.psi.PsiReferenceExpression;
  21 import com.intellij.psi.PsiVariable;
  22 import org.jetbrains.annotations.NotNull;
  23
  24 public class VariableUsedVisitor extends JavaRecursiveElementVisitor {
  25
  26     private boolean used = false;
  27     @NotNull private final PsiVariable variable;
  28
  29     public VariableUsedVisitor(@NotNull PsiVariable variable){
  30         super();
  31         this.variable = variable;
  32     }
  33
  34     @Override public void visitElement(@NotNull PsiElement element){
  35         if(!used){
  36             super.visitElement(element);
  37         }
  38     }
  39
  40     @Override public void visitReferenceExpression(@NotNull PsiReferenceExpression ref){
  41         if(used){
  42             return;
  43         }
  44         super.visitReferenceExpression(ref);
  45         final PsiElement referent = ref.resolve();
  46         if(referent == null){
  47             return;
  48         }
  49         if(referent.equals(variable)){
  50             used = true;
  51         }
  52     }
  53
  54     public boolean isUsed(){
  55         return used;
  56     }
  57 }