Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
StringLiteralEqualityCheck |
|
| 2.0;2 |
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.coding; | |
20 | ||
21 | import com.puppycrawl.tools.checkstyle.api.Check; | |
22 | import com.puppycrawl.tools.checkstyle.api.TokenTypes; | |
23 | import com.puppycrawl.tools.checkstyle.api.DetailAST; | |
24 | import antlr.collections.AST; | |
25 | ||
26 | /** | |
27 | * <p>Checks that string literals are not used with | |
28 | * <code>==</code> or <code>!=</code>. | |
29 | * </p> | |
30 | * <p> | |
31 | * Rationale: Novice Java programmers often use code like | |
32 | * <code>if (x == "something")</code> when they mean | |
33 | * <code>if ("something".equals(x))</code>. | |
34 | * </p> | |
35 | * | |
36 | * @author Lars Kühne | |
37 | */ | |
38 | 1 | public class StringLiteralEqualityCheck extends Check |
39 | { | |
40 | @Override | |
41 | public int[] getDefaultTokens() | |
42 | { | |
43 | 1 | return new int[] {TokenTypes.EQUAL, TokenTypes.NOT_EQUAL}; |
44 | } | |
45 | ||
46 | @Override | |
47 | public void visitToken(DetailAST aAST) | |
48 | { | |
49 | // no need to check for nulls here, == and != always have two children | |
50 | 5 | final AST firstChild = aAST.getFirstChild(); |
51 | 5 | final AST secondChild = firstChild.getNextSibling(); |
52 | ||
53 | 5 | if ((firstChild.getType() == TokenTypes.STRING_LITERAL) |
54 | || (secondChild.getType() == TokenTypes.STRING_LITERAL)) | |
55 | { | |
56 | 3 | log(aAST.getLineNo(), aAST.getColumnNo(), |
57 | "string.literal.equality", aAST.getText()); | |
58 | } | |
59 | 5 | } |
60 | } |