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.indentation;
  
  import java.util.BitSet;
  
  import com.puppycrawl.tools.checkstyle.api.DetailAST;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
  
  /**
   * Handler for a list of statements.
   *
   */
  public class SlistHandler extends BlockParentHandler {
  
      /**
       * Parent token types.
       */
      private static final BitSet PARENT_TOKEN_TYPES = TokenUtil.asBitSet(
          TokenTypes.CTOR_DEF,
          TokenTypes.METHOD_DEF,
          TokenTypes.STATIC_INIT,
          TokenTypes.LITERAL_SYNCHRONIZED,
          TokenTypes.LITERAL_IF,
          TokenTypes.LITERAL_WHILE,
          TokenTypes.LITERAL_DO,
          TokenTypes.LITERAL_FOR,
          TokenTypes.LITERAL_ELSE,
          TokenTypes.LITERAL_TRY,
          TokenTypes.LITERAL_CATCH,
          TokenTypes.LITERAL_FINALLY,
          TokenTypes.COMPACT_CTOR_DEF
      );
  
      /**
       * Construct an instance of this handler with the given indentation check,
       * abstract syntax tree, and parent handler.
       *
       * @param indentCheck   the indentation check
       * @param ast           the abstract syntax tree
       * @param parent        the parent handler
       */
      public SlistHandler(IndentationCheck indentCheck,
          DetailAST ast, AbstractExpressionHandler parent) {
          super(indentCheck, "block", ast, parent);
      }
  
      @Override
      public IndentLevel getSuggestedChildIndent(AbstractExpressionHandler child) {
          // this is:
          //  switch (var) {
          //     case 3: {
          //        break;
          //     }
          //  }
          //  ... the case SLIST is followed by a user-created SLIST and
          //  preceded by a switch
  
          final IndentLevel result;
          // if our parent is a block handler we want to be transparent
          if (getParent() instanceof BlockParentHandler
                  && !(getParent() instanceof SlistHandler)
              || child instanceof SlistHandler
                  && getParent() instanceof CaseHandler) {
              result = getParent().getSuggestedChildIndent(child);
          }
          else {
              result = super.getSuggestedChildIndent(child);
          }
          return result;
      }
  
      @Override
      protected DetailAST getListChild() {
          return getMainAst();
      }
  
      @Override
      protected DetailAST getLeftCurly() {
          return getMainAst();
      }
  
      @Override
      protected DetailAST getRightCurly() {
          return getMainAst().findFirstToken(TokenTypes.RCURLY);
      }
  
      @Override
      protected DetailAST getTopLevelAst() {
          return null;
      }
  
      /**
       * Determine if the expression we are handling has a block parent.
       *
       * @return true if it does, false otherwise
       */
      private boolean hasBlockParent() {
          final int parentType = getMainAst().getParent().getType();
          return PARENT_TOKEN_TYPES.get(parentType);
      }
  
      @Override
      public void checkIndentation() {
          // only need to check this if parent is not
          // an if, else, while, do, ctor, method
          if (!hasBlockParent() && !isSameLineCaseGroup()) {
              super.checkIndentation();
          }
      }
  
      /**
       * Checks if SLIST node is placed at the same line as CASE_GROUP node.
       *
       * @return true, if SLIST node is places at the same line as CASE_GROUP node.
       */
      private boolean isSameLineCaseGroup() {
          final DetailAST parentNode = getMainAst().getParent();
          return parentNode.getType() == TokenTypes.CASE_GROUP
              && TokenUtil.areOnSameLine(getMainAst(), parentNode);
      }
  
  }
  