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
  ///////////////////////////////////////////////////////////////////////////////////////////////
  
  /**
   * User interface classes for CheckStyle. Currently, this is mainly a gui to aid
   * Check developers.
   *
   * <p>This is definitely work in progress. Here are some ideas where
   * <strong>you</strong> could help:
   * <ul>
   *   <li>
   *     Add a read only editor field that highlights the selected AST node.
   *   </li>
   *   <li>
   *     Clicking in the editor field could open the corresponding tree path.
   *   </li>
   *   <li>
   *     Add a configuration GUI that can be used in all IDE plugins
   *     (well, err.., except Eclipse).
   *   </li>
   *   <li>
   *     Add ability to execute individual Checks and display the violation messages.
   *   </li>
   *   <li>
   *     Add a GUI for the
   *     {@link com.puppycrawl.tools.checkstyle.api.FileContents}.
   *   </li>
   *   <li>
   *     Add ability to define a Check by example (another one of those crazy
   *     ideas... :-)
   *   </li>
   * </ul>
   */
  package com.puppycrawl.tools.checkstyle.gui;
  