Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
EmptyBlockCheck |
|
| 4.0;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 | * <module name="EmptyBlock"/> | |
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 | * <module name="EmptyBlock"> | |
53 | * <property name="tokens" value="LITERAL_CATCH"/> | |
54 | * <property name="option" value="text"/> | |
55 | * </module> | |
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 | } |