plugins/InspectionGadgets/src/com/siyeh/ig/bugs/InstanceofIncompatibleInterfaceInspection.java

   1 /*
   2  * Copyright 2003-2007 Dave Griffith, Bas Leijdekkers
   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.bugs;
  17
  18 import com.intellij.psi.*;
  19 import com.siyeh.InspectionGadgetsBundle;
  20 import com.siyeh.ig.BaseInspection;
  21 import com.siyeh.ig.BaseInspectionVisitor;
  22 import com.siyeh.ig.psiutils.InheritanceUtil;
  23 import org.jetbrains.annotations.NotNull;
  24
  25 public class InstanceofIncompatibleInterfaceInspection
  26         extends BaseInspection {
  27
  28     @NotNull
  29     public String getDisplayName(){
  30         return InspectionGadgetsBundle.message(
  31                 "instanceof.with.incompatible.interface.display.name");
  32     }
  33
  34     @NotNull
  35     public String buildErrorString(Object... infos){
  36         return InspectionGadgetsBundle.message(
  37                 "instanceof.with.incompatible.interface.problem.descriptor");
  38     }
  39
  40     public BaseInspectionVisitor buildVisitor(){
  41         return new InstanceofIncompatibleInterfaceVisitor();
  42     }
  43
  44     private static class InstanceofIncompatibleInterfaceVisitor
  45             extends BaseInspectionVisitor{
  46
  47         @Override public void visitInstanceOfExpression(
  48                 @NotNull PsiInstanceOfExpression expression){
  49             super.visitInstanceOfExpression(expression);
  50             final PsiTypeElement castTypeElement = expression.getCheckType();
  51             if(castTypeElement == null){
  52                 return;
  53             }
  54             final PsiType castType = castTypeElement.getType();
  55             if(!(castType instanceof PsiClassType)){
  56                 return;
  57             }
  58             final PsiClassType castClassType = (PsiClassType)castType;
  59             final PsiExpression operand = expression.getOperand();
  60             final PsiType operandType = operand.getType();
  61             if(!(operandType instanceof PsiClassType)){
  62                 return;
  63             }
  64             final PsiClassType operandClassType = (PsiClassType)operandType;
  65             final PsiClass castClass = castClassType.resolve();
  66             if(castClass == null){
  67                 return;
  68             }
  69             if(!castClass.isInterface()){
  70                 return;
  71             }
  72             final PsiClass operandClass = operandClassType.resolve();
  73             if(operandClass == null){
  74                 return;
  75             }
  76             if(operandClass.isInterface()){
  77                 return;
  78             }
  79             if(InheritanceUtil.existsMutualSubclass(operandClass, castClass)){
  80                 return;
  81             }
  82             registerError(castTypeElement);
  83         }
  84     }
  85 }