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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.coding;
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 if call to superclass constructor without arguments is present.
30   * Such invocation is redundant because constructor body implicitly
31   * begins with a superclass constructor invocation {@code super();}
32   * See <a href="https://docs.oracle.com/javase/specs/jls/se13/html/jls-8.html#jls-8.8.7">
33   * specification</a> for detailed information.
34   * </div>
35   *
36   * <p>
37   * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
38   * </p>
39   *
40   * <p>
41   * Violation Message Keys:
42   * </p>
43   * <ul>
44   * <li>
45   * {@code super.constructor.call}
46   * </li>
47   * </ul>
48   *
49   * @since 8.29
50   */
51  @StatelessCheck
52  public final class AvoidNoArgumentSuperConstructorCallCheck extends AbstractCheck {
53  
54      /**
55       * A key is pointing to the warning message text in "messages.properties"
56       * file.
57       */
58      public static final String MSG_CTOR = "super.constructor.call";
59  
60      @Override
61      public int[] getDefaultTokens() {
62          return getRequiredTokens();
63      }
64  
65      @Override
66      public int[] getAcceptableTokens() {
67          return getRequiredTokens();
68      }
69  
70      @Override
71      public int[] getRequiredTokens() {
72          return new int[] {
73              TokenTypes.SUPER_CTOR_CALL,
74          };
75      }
76  
77      @Override
78      public void visitToken(DetailAST ast) {
79          if (ast.getFirstChild().getType() == TokenTypes.LPAREN
80                  && ast.findFirstToken(TokenTypes.ELIST).getChildCount() == 0) {
81              log(ast, MSG_CTOR);
82          }
83      }
84  }