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.whitespace;
  
  import java.util.Locale;
  
  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.utils.CodePointUtil;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  /**
   * <p>Abstract class for checking the padding of parentheses. That is whether a
   * space is required after a left parenthesis and before a right parenthesis,
   * or such spaces are forbidden.
   * </p>
   */
  @StatelessCheck
  public abstract class AbstractParenPadCheck
      extends AbstractCheck {
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_WS_FOLLOWED = "ws.followed";
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_WS_NOT_FOLLOWED = "ws.notFollowed";
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_WS_PRECEDED = "ws.preceded";
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_WS_NOT_PRECEDED = "ws.notPreceded";
  
      /** Open parenthesis literal. */
      private static final char OPEN_PARENTHESIS = '(';
  
      /** Close parenthesis literal. */
      private static final char CLOSE_PARENTHESIS = ')';
  
      /** The policy to enforce. */
      private PadOption option = PadOption.NOSPACE;
  
      /**
       * Set the option to enforce.
       *
       * @param optionStr string to decode option from
       * @throws IllegalArgumentException if unable to decode
       */
      public void setOption(String optionStr) {
          option = PadOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
      }
  
      /**
       * Process a token representing a left parentheses.
       *
       * @param ast the token representing a left parentheses
       */
      protected void processLeft(DetailAST ast) {
          final int[] line = getLineCodePoints(ast.getLineNo() - 1);
          final int after = ast.getColumnNo() + 1;
  
          if (after < line.length) {
              final boolean hasWhitespaceAfter =
                      CommonUtil.isCodePointWhitespace(line, after);
              if (option == PadOption.NOSPACE && hasWhitespaceAfter) {
                  log(ast, MSG_WS_FOLLOWED, OPEN_PARENTHESIS);
              }
              else if (option == PadOption.SPACE && !hasWhitespaceAfter
                       && line[after] != CLOSE_PARENTHESIS) {
                  log(ast, MSG_WS_NOT_FOLLOWED, OPEN_PARENTHESIS);
              }
          }
      }
  
      /**
       * Process a token representing a right parentheses.
       *
       * @param ast the token representing a right parentheses
       */
      protected void processRight(DetailAST ast) {
          final int before = ast.getColumnNo() - 1;
          if (before >= 0) {
              final int[] line = getLineCodePoints(ast.getLineNo() - 1);
              final boolean hasPrecedingWhitespace =
                      CommonUtil.isCodePointWhitespace(line, before);
  
              if (option == PadOption.NOSPACE && hasPrecedingWhitespace
                  && !CodePointUtil.hasWhitespaceBefore(before, line)) {
                  log(ast, MSG_WS_PRECEDED, CLOSE_PARENTHESIS);
              }
              else if (option == PadOption.SPACE && !hasPrecedingWhitespace
                  && line[before] != OPEN_PARENTHESIS) {
                  log(ast, MSG_WS_NOT_PRECEDED, CLOSE_PARENTHESIS);
              }
          }
      }
  
  }
  