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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) 2001-2025 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 }