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