code: ///////////////////////////////////////////////////////////////////////////////////////////////
  // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
  // Copyright (C) 2001-2023 the original author or authors.
  //
  // This library is free software; you can redistribute it and/or
  // modify it under the terms of the GNU Lesser General Public
  // License as published by the Free Software Foundation; either
  // version 2.1 of the License, or (at your option) any later version.
  //
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  // Lesser General Public License for more details.
  //
  // You should have received a copy of the GNU Lesser General Public
  // License along with this library; if not, write to the Free Software
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  ///////////////////////////////////////////////////////////////////////////////////////////////
  
  package com.puppycrawl.tools.checkstyle.checks.coding;
  
  import com.puppycrawl.tools.checkstyle.StatelessCheck;
  import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
  import com.puppycrawl.tools.checkstyle.api.DetailAST;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  
  /**
   * <p>
   * Checks if call to superclass constructor without arguments is present.
   * Such invocation is redundant because constructor body implicitly
   * begins with a superclass constructor invocation {@code super();}
   * See <a href="https://docs.oracle.com/javase/specs/jls/se13/html/jls-8.html#jls-8.8.7">
   * specification</a> for detailed information.
   * </p>
   * <p>
   * To configure the check:
   * </p>
   * <pre>
   * &lt;module name=&quot;AvoidNoArgumentSuperConstructorCall&quot;/&gt;
   * </pre>
   * <p>
   * Example of violations
   * </p>
   * <pre>
   * class MyClass extends SomeOtherClass {
   *     MyClass() {
   *         super(); // violation
   *     }
   *
   *     MyClass(int arg) {
   *         super(arg); // OK, call with argument have to be explicit
   *     }
   *
   *     MyClass(long arg) {
   *         // OK, call is implicit
   *     }
   * }
   * </pre>
   * <p>
   * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
   * </p>
   * <p>
   * Violation Message Keys:
   * </p>
   * <ul>
   * <li>
   * {@code super.constructor.call}
   * </li>
   * </ul>
   *
   * @since 8.29
   */
  @StatelessCheck
  public final class AvoidNoArgumentSuperConstructorCallCheck extends AbstractCheck {
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_CTOR = "super.constructor.call";
  
      @Override
      public int[] getDefaultTokens() {
          return getRequiredTokens();
      }
  
      @Override
      public int[] getAcceptableTokens() {
          return getRequiredTokens();
      }
  
      @Override
      public int[] getRequiredTokens() {
          return new int[] {
              TokenTypes.SUPER_CTOR_CALL,
          };
      }
  
      @Override
      public void visitToken(DetailAST ast) {
          if (ast.getFirstChild().getType() == TokenTypes.LPAREN
                  && ast.findFirstToken(TokenTypes.ELIST).getChildCount() == 0) {
              log(ast, MSG_CTOR);
          }
      }
  }
  