Coverage Report - com.puppycrawl.tools.checkstyle.checks.blocks.EmptyBlockCheck
 
Classes in this File Line Coverage Branch Coverage Complexity
EmptyBlockCheck
96%
30/31
79%
19/24
4
 
 1  
 ////////////////////////////////////////////////////////////////////////////////
 2  
 // checkstyle: Checks Java source code for adherence to a set of rules.
 3  
 // Copyright (C) 2001-2014  Oliver Burn
 4  
 //
 5  
 // This library is free software; you can redistribute it and/or
 6  
 // modify it under the terms of the GNU Lesser General Public
 7  
 // License as published by the Free Software Foundation; either
 8  
 // version 2.1 of the License, or (at your option) any later version.
 9  
 //
 10  
 // This library is distributed in the hope that it will be useful,
 11  
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 12  
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 13  
 // Lesser General Public License for more details.
 14  
 //
 15  
 // You should have received a copy of the GNU Lesser General Public
 16  
 // License along with this library; if not, write to the Free Software
 17  
 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 18  
 ////////////////////////////////////////////////////////////////////////////////
 19  
 package com.puppycrawl.tools.checkstyle.checks.blocks;
 20  
 
 21  
 import com.puppycrawl.tools.checkstyle.api.DetailAST;
 22  
 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
 23  
 import com.puppycrawl.tools.checkstyle.checks.AbstractOptionCheck;
 24  
 
 25  
 /**
 26  
  * Checks for empty blocks. The policy to verify is specified using the {@link
 27  
  * BlockOption} class and defaults to {@link BlockOption#STMT}.
 28  
  *
 29  
  * <p> By default the check will check the following blocks:
 30  
  *  {@link TokenTypes#LITERAL_WHILE LITERAL_WHILE},
 31  
  *  {@link TokenTypes#LITERAL_TRY LITERAL_TRY},
 32  
  *  {@link TokenTypes#LITERAL_CATCH LITERAL_CATCH},
 33  
  *  {@link TokenTypes#LITERAL_FINALLY LITERAL_FINALLY},
 34  
  *  {@link TokenTypes#LITERAL_DO LITERAL_DO},
 35  
  *  {@link TokenTypes#LITERAL_IF LITERAL_IF},
 36  
  *  {@link TokenTypes#LITERAL_ELSE LITERAL_ELSE},
 37  
  *  {@link TokenTypes#LITERAL_FOR LITERAL_FOR},
 38  
  *  {@link TokenTypes#STATIC_INIT STATIC_INIT}.
 39  
  * </p>
 40  
  *
 41  
  * <p> An example of how to configure the check is:
 42  
  * </p>
 43  
  * <pre>
 44  
  * &lt;module name="EmptyBlock"/&gt;
 45  
  * </pre>
 46  
  *
 47  
  * <p> An example of how to configure the check for the {@link
 48  
  * BlockOption#TEXT} policy and only catch blocks is:
 49  
  * </p>
 50  
  *
 51  
  * <pre>
 52  
  * &lt;module name="EmptyBlock"&gt;
 53  
  *    &lt;property name="tokens" value="LITERAL_CATCH"/&gt;
 54  
  *    &lt;property name="option" value="text"/&gt;
 55  
  * &lt;/module&gt;
 56  
  * </pre>
 57  
  *
 58  
  * @author Lars Kühne
 59  
  */
 60  
 public class EmptyBlockCheck
 61  
     extends AbstractOptionCheck<BlockOption>
 62  
 {
 63  
     /**
 64  
      * Creates a new <code>EmptyBlockCheck</code> instance.
 65  
      */
 66  
     public EmptyBlockCheck()
 67  
     {
 68  3
         super(BlockOption.STMT, BlockOption.class);
 69  3
     }
 70  
 
 71  
     @Override
 72  
     public int[] getDefaultTokens()
 73  
     {
 74  3
         return new int[] {
 75  
             TokenTypes.LITERAL_WHILE,
 76  
             TokenTypes.LITERAL_TRY,
 77  
             TokenTypes.LITERAL_CATCH,
 78  
             TokenTypes.LITERAL_FINALLY,
 79  
             TokenTypes.LITERAL_DO,
 80  
             TokenTypes.LITERAL_IF,
 81  
             TokenTypes.LITERAL_ELSE,
 82  
             TokenTypes.LITERAL_FOR,
 83  
             TokenTypes.INSTANCE_INIT,
 84  
             TokenTypes.STATIC_INIT,
 85  
             // TODO: need to handle....
 86  
             //TokenTypes.LITERAL_SWITCH,
 87  
             //TODO: does this handle TokenTypes.LITERAL_SYNCHRONIZED?
 88  
         };
 89  
     }
 90  
 
 91  
     @Override
 92  
     public void visitToken(DetailAST aAST)
 93  
     {
 94  57
         final DetailAST slistAST = aAST.findFirstToken(TokenTypes.SLIST);
 95  57
         if (slistAST != null) {
 96  54
             if (getAbstractOption() == BlockOption.STMT) {
 97  36
                 if (slistAST.getChildCount() <= 1) {
 98  20
                     log(slistAST.getLineNo(),
 99  
                         slistAST.getColumnNo(),
 100  
                         "block.noStmt",
 101  
                         aAST.getText());
 102  
                 }
 103  
             }
 104  18
             else if (getAbstractOption() == BlockOption.TEXT
 105  
                     && !hasText(slistAST))
 106  
             {
 107  6
                 log(slistAST.getLineNo(),
 108  
                     slistAST.getColumnNo(),
 109  
                     "block.empty",
 110  
                     aAST.getText());
 111  
             }
 112  
         }
 113  57
     }
 114  
 
 115  
     /**
 116  
      * @param aSlistAST a <code>DetailAST</code> value
 117  
      * @return whether the SLIST token contains any text.
 118  
      */
 119  
     protected boolean hasText(final DetailAST aSlistAST)
 120  
     {
 121  18
         boolean retVal = false;
 122  
 
 123  18
         final DetailAST rcurlyAST = aSlistAST.findFirstToken(TokenTypes.RCURLY);
 124  18
         if (rcurlyAST != null) {
 125  18
             final int slistLineNo = aSlistAST.getLineNo();
 126  18
             final int slistColNo = aSlistAST.getColumnNo();
 127  18
             final int rcurlyLineNo = rcurlyAST.getLineNo();
 128  18
             final int rcurlyColNo = rcurlyAST.getColumnNo();
 129  18
             final String[] lines = getLines();
 130  18
             if (slistLineNo == rcurlyLineNo) {
 131  
                 // Handle braces on the same line
 132  3
                 final String txt = lines[slistLineNo - 1]
 133  
                     .substring(slistColNo + 1, rcurlyColNo);
 134  3
                 if (txt.trim().length() != 0) {
 135  1
                     retVal = true;
 136  
                 }
 137  3
             }
 138  
             else {
 139  
                 // check only whitespace of first & last lines
 140  15
                 if ((lines[slistLineNo - 1]
 141  
                      .substring(slistColNo + 1).trim().length() != 0)
 142  
                     || (lines[rcurlyLineNo - 1]
 143  
                         .substring(0, rcurlyColNo).trim().length() != 0))
 144  
                 {
 145  0
                     retVal = true;
 146  
                 }
 147  
                 else {
 148  
                     // check if all lines are also only whitespace
 149  15
                     for (int i = slistLineNo; i < (rcurlyLineNo - 1); i++) {
 150  11
                         if (lines[i].trim().length() > 0) {
 151  11
                             retVal = true;
 152  11
                             break;
 153  
                         }
 154  
                     }
 155  
                 }
 156  
             }
 157  
         }
 158  18
         return retVal;
 159  
     }
 160  
 }