1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2024 the original author or authors.
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
20 package com.puppycrawl.tools.checkstyle.checks;
21
22 import com.puppycrawl.tools.checkstyle.StatelessCheck;
23 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
24 import com.puppycrawl.tools.checkstyle.api.DetailAST;
25 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
26
27 /**
28 * <div>
29 * Checks the style of array type definitions.
30 * Some like Java style: {@code public static void main(String[] args)}
31 * and some like C style: {@code public static void main(String args[])}.
32 * </div>
33 *
34 * <p>
35 * By default, the Check enforces Java style.
36 * </p>
37 *
38 * <p>
39 * This check strictly enforces only Java style for method return types regardless
40 * of the value for 'javaStyle'. For example, {@code byte[] getData()}.
41 * This is because C doesn't compile methods with array declarations on the name.
42 * </p>
43 * <ul>
44 * <li>
45 * Property {@code javaStyle} - Control whether to enforce Java style (true) or C style (false).
46 * Type is {@code boolean}.
47 * Default value is {@code true}.
48 * </li>
49 * </ul>
50 *
51 * <p>
52 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
53 * </p>
54 *
55 * <p>
56 * Violation Message Keys:
57 * </p>
58 * <ul>
59 * <li>
60 * {@code array.type.style}
61 * </li>
62 * </ul>
63 *
64 * @since 3.1
65 */
66 @StatelessCheck
67 public class ArrayTypeStyleCheck extends AbstractCheck {
68
69 /**
70 * A key is pointing to the warning message text in "messages.properties"
71 * file.
72 */
73 public static final String MSG_KEY = "array.type.style";
74
75 /** Control whether to enforce Java style (true) or C style (false). */
76 private boolean javaStyle = true;
77
78 @Override
79 public int[] getDefaultTokens() {
80 return getRequiredTokens();
81 }
82
83 @Override
84 public int[] getAcceptableTokens() {
85 return getRequiredTokens();
86 }
87
88 @Override
89 public int[] getRequiredTokens() {
90 return new int[] {TokenTypes.ARRAY_DECLARATOR};
91 }
92
93 @Override
94 public void visitToken(DetailAST ast) {
95 final DetailAST typeAST = ast.getParent();
96 final DetailAST identAst = typeAST.getNextSibling();
97 // If identAst is null, we have a 'LITERAL_NEW' expression, i.e. 'new int[2][2]'
98 if (identAst != null) {
99 final boolean isMethod = typeAST.getParent().getType() == TokenTypes.METHOD_DEF;
100 final boolean isJavaStyle = identAst.getLineNo() > ast.getLineNo()
101 || identAst.getColumnNo() - ast.getColumnNo() > -1;
102
103 // force all methods to be Java style (see note in top Javadoc)
104 final boolean isMethodViolation = isMethod && !isJavaStyle;
105 final boolean isVariableViolation = !isMethod
106 && isJavaStyle != javaStyle;
107
108 if (isMethodViolation || isVariableViolation) {
109 log(ast, MSG_KEY);
110 }
111 }
112 }
113
114 /**
115 * Setter to control whether to enforce Java style (true) or C style (false).
116 *
117 * @param javaStyle true if Java style should be used.
118 * @since 3.1
119 */
120 public void setJavaStyle(boolean javaStyle) {
121 this.javaStyle = javaStyle;
122 }
123
124 }