plugins/InspectionGadgets/src/com/siyeh/ig/bugs/EmptyStatementBodyInspection.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.intellij.psi.util.PsiUtil;
  20 import com.siyeh.InspectionGadgetsBundle;
  21 import com.siyeh.ig.BaseInspection;
  22 import com.siyeh.ig.BaseInspectionVisitor;
  23 import com.siyeh.ig.ui.SingleCheckboxOptionsPanel;
  24 import org.jetbrains.annotations.NotNull;
  25
  26 import javax.swing.*;
  27
  28 public class EmptyStatementBodyInspection extends BaseInspection {
  29
  30     /** @noinspection PublicField*/
  31     public boolean m_reportEmptyBlocks = false;
  32
  33     @NotNull
  34     public String getID(){
  35         return "StatementWithEmptyBody";
  36     }
  37
  38     @NotNull
  39     public String getDisplayName(){
  40         return InspectionGadgetsBundle.message(
  41                 "statement.with.empty.body.display.name");
  42     }
  43
  44     @NotNull
  45     public String buildErrorString(Object... infos){
  46         return InspectionGadgetsBundle.message(
  47                 "statement.with.empty.body.problem.descriptor");
  48     }
  49
  50     public boolean isEnabledByDefault(){
  51         return true;
  52     }
  53
  54     public JComponent createOptionsPanel(){
  55         return new SingleCheckboxOptionsPanel(
  56                 InspectionGadgetsBundle.message(
  57                         "statement.with.empty.body.include.option"),
  58                 this, "m_reportEmptyBlocks");
  59     }
  60
  61     public BaseInspectionVisitor buildVisitor() {
  62         return new EmptyStatementVisitor();
  63     }
  64
  65     private class EmptyStatementVisitor extends BaseInspectionVisitor {
  66
  67         @Override public void visitDoWhileStatement(
  68                 @NotNull PsiDoWhileStatement statement) {
  69             super.visitDoWhileStatement(statement);
  70             if (PsiUtil.isInJspFile(statement.getContainingFile())) {
  71                 return;
  72             }
  73             final PsiStatement body = statement.getBody();
  74             if (body == null || !isEmpty(body)) {
  75                 return;
  76             }
  77             registerStatementError(statement);
  78         }
  79
  80         @Override public void visitWhileStatement(@NotNull PsiWhileStatement statement) {
  81             super.visitWhileStatement(statement);
  82             if (PsiUtil.isInJspFile(statement.getContainingFile())) {
  83                 return;
  84             }
  85             final PsiStatement body = statement.getBody();
  86             if (body == null || !isEmpty(body)) {
  87                 return;
  88             }
  89             registerStatementError(statement);
  90         }
  91
  92         @Override public void visitForStatement(@NotNull PsiForStatement statement) {
  93             super.visitForStatement(statement);
  94             if (PsiUtil.isInJspFile(statement.getContainingFile())) {
  95                 return;
  96             }
  97             final PsiStatement body = statement.getBody();
  98             if (body == null || !isEmpty(body)) {
  99                 return;
 100             }
 101             registerStatementError(statement);
 102         }
 103
 104         @Override public void visitForeachStatement(
 105                 @NotNull PsiForeachStatement statement) {
 106             super.visitForeachStatement(statement);
 107             if (PsiUtil.isInJspFile(statement.getContainingFile())) {
 108                 return;
 109             }
 110             final PsiStatement body = statement.getBody();
 111             if (body == null || !isEmpty(body)) {
 112                 return;
 113             }
 114             registerStatementError(statement);
 115         }
 116
 117         @Override public void visitIfStatement(@NotNull PsiIfStatement statement) {
 118             super.visitIfStatement(statement);
 119             if (PsiUtil.isInJspFile(statement.getContainingFile())) {
 120                 return;
 121             }
 122             final PsiStatement thenBranch = statement.getThenBranch();
 123             if (thenBranch != null && isEmpty(thenBranch)) {
 124                 registerStatementError(statement);
 125                 return;
 126             }
 127             final PsiStatement elseBranch = statement.getElseBranch();
 128             if (elseBranch != null && isEmpty(elseBranch)) {
 129                 final PsiElement elseToken = statement.getElseElement();
 130                 if (elseToken == null) {
 131                     return;
 132                 }
 133                 registerError(elseToken);
 134             }
 135         }
 136
 137         private boolean isEmpty(PsiElement body) {
 138             if (body instanceof PsiEmptyStatement) {
 139                 return true;
 140             } else if (m_reportEmptyBlocks &&
 141                     body instanceof PsiBlockStatement) {
 142                 final PsiBlockStatement block = (PsiBlockStatement) body;
 143                 final PsiCodeBlock codeBlock = block.getCodeBlock();
 144                 return codeBlockIsEmpty(codeBlock);
 145             } else if (body instanceof PsiCodeBlock) {
 146                 final PsiCodeBlock codeBlock = (PsiCodeBlock) body;
 147                 return codeBlockIsEmpty(codeBlock);
 148             }
 149             return false;
 150         }
 151
 152         private boolean codeBlockIsEmpty(PsiCodeBlock codeBlock) {
 153             final PsiStatement[] statements = codeBlock.getStatements();
 154             return statements.length == 0;
 155         }
 156     }
 157 }