1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2026 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 *
44 * @since 3.1
45 */
46 @StatelessCheck
47 public class ArrayTypeStyleCheck extends AbstractCheck {
48
49 /**
50 * A key is pointing to the warning message text in "messages.properties"
51 * file.
52 */
53 public static final String MSG_KEY = "array.type.style";
54
55 /** Control whether to enforce Java style (true) or C style (false). */
56 private boolean javaStyle = true;
57
58 /**
59 * Creates a new {@code ArrayTypeStyleCheck} instance.
60 */
61 public ArrayTypeStyleCheck() {
62 // no code by default
63 }
64
65 @Override
66 public int[] getDefaultTokens() {
67 return getRequiredTokens();
68 }
69
70 @Override
71 public int[] getAcceptableTokens() {
72 return getRequiredTokens();
73 }
74
75 @Override
76 public int[] getRequiredTokens() {
77 return new int[] {TokenTypes.ARRAY_DECLARATOR};
78 }
79
80 @Override
81 public void visitToken(DetailAST ast) {
82 final DetailAST typeAST = ast.getParent();
83 final DetailAST identAst = typeAST.getNextSibling();
84 // If identAst is null, we have a 'LITERAL_NEW' expression, i.e. 'new int[2][2]'
85 if (identAst != null) {
86 final boolean isMethod = typeAST.getParent().getType() == TokenTypes.METHOD_DEF;
87 final boolean isJavaStyle = identAst.getLineNo() > ast.getLineNo()
88 || identAst.getColumnNo() - ast.getColumnNo() > -1;
89
90 // force all methods to be Java style (see note in top Javadoc)
91 final boolean isMethodViolation = isMethod && !isJavaStyle;
92 final boolean isVariableViolation = !isMethod
93 && isJavaStyle != javaStyle;
94
95 if (isMethodViolation || isVariableViolation) {
96 log(ast, MSG_KEY);
97 }
98 }
99 }
100
101 /**
102 * Setter to control whether to enforce Java style (true) or C style (false).
103 *
104 * @param javaStyle true if Java style should be used.
105 * @since 3.1
106 */
107 public void setJavaStyle(boolean javaStyle) {
108 this.javaStyle = javaStyle;
109 }
110
111 }