plugins/InspectionGadgets/src/com/siyeh/ig/bugs/CastToIncompatibleInterfaceInspection.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 CastToIncompatibleInterfaceInspection extends BaseInspection {
  26
  27     @NotNull
  28     public String getDisplayName(){
  29         return InspectionGadgetsBundle.message(
  30                 "casting.to.incompatible.interface.display.name");
  31     }
  32
  33     @NotNull
  34     public String buildErrorString(Object... infos){
  35         return InspectionGadgetsBundle.message(
  36                 "casting.to.incompatible.interface.problem.descriptor");
  37     }
  38
  39     public BaseInspectionVisitor buildVisitor(){
  40         return new CastToIncompatibleInterfaceVisitor();
  41     }
  42
  43     private static class CastToIncompatibleInterfaceVisitor
  44             extends BaseInspectionVisitor{
  45
  46         @Override public void visitTypeCastExpression(
  47                 @NotNull PsiTypeCastExpression expression){
  48             super.visitTypeCastExpression(expression);
  49             final PsiTypeElement castTypeElement = expression.getCastType();
  50             if(castTypeElement == null){
  51                 return;
  52             }
  53             final PsiType castType = castTypeElement.getType();
  54             if(!(castType instanceof PsiClassType)){
  55                 return;
  56             }
  57             final PsiClassType castClassType = (PsiClassType)castType;
  58             final PsiExpression operand = expression.getOperand();
  59             if(operand == null){
  60                 return;
  61             }
  62             final PsiType operandType = operand.getType();
  63             if(!(operandType instanceof PsiClassType)){
  64                 return;
  65             }
  66             final PsiClassType operandClassType = (PsiClassType)operandType;
  67             final PsiClass castClass = castClassType.resolve();
  68             if(castClass == null){
  69                 return;
  70             }
  71             if(!castClass.isInterface()){
  72                 return;
  73             }
  74             final PsiClass operandClass = operandClassType.resolve();
  75             if(operandClass == null){
  76                 return;
  77             }
  78             if(operandClass.isInterface()){
  79                 return;
  80             }
  81             if(InheritanceUtil.existsMutualSubclass(operandClass, castClass)){
  82                 return;
  83             }
  84             registerError(castTypeElement);
  85         }
  86     }
  87 }