1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2025 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 @Override
59 public int[] getDefaultTokens() {
60 return getRequiredTokens();
61 }
62
63 @Override
64 public int[] getAcceptableTokens() {
65 return getRequiredTokens();
66 }
67
68 @Override
69 public int[] getRequiredTokens() {
70 return new int[] {TokenTypes.ARRAY_DECLARATOR};
71 }
72
73 @Override
74 public void visitToken(DetailAST ast) {
75 final DetailAST typeAST = ast.getParent();
76 final DetailAST identAst = typeAST.getNextSibling();
77 // If identAst is null, we have a 'LITERAL_NEW' expression, i.e. 'new int[2][2]'
78 if (identAst != null) {
79 final boolean isMethod = typeAST.getParent().getType() == TokenTypes.METHOD_DEF;
80 final boolean isJavaStyle = identAst.getLineNo() > ast.getLineNo()
81 || identAst.getColumnNo() - ast.getColumnNo() > -1;
82
83 // force all methods to be Java style (see note in top Javadoc)
84 final boolean isMethodViolation = isMethod && !isJavaStyle;
85 final boolean isVariableViolation = !isMethod
86 && isJavaStyle != javaStyle;
87
88 if (isMethodViolation || isVariableViolation) {
89 log(ast, MSG_KEY);
90 }
91 }
92 }
93
94 /**
95 * Setter to control whether to enforce Java style (true) or C style (false).
96 *
97 * @param javaStyle true if Java style should be used.
98 * @since 3.1
99 */
100 public void setJavaStyle(boolean javaStyle) {
101 this.javaStyle = javaStyle;
102 }
103
104 }