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.design;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  import static com.puppycrawl.tools.checkstyle.checks.design.MutableExceptionCheck.MSG_KEY;
  
  import java.io.File;
  import java.util.Arrays;
  import java.util.List;
  
  import org.antlr.v4.runtime.CommonToken;
  import org.junit.jupiter.api.Test;
  
  import com.google.common.collect.ImmutableMap;
  import com.puppycrawl.tools.checkstyle.AbstractModuleTestSupport;
  import com.puppycrawl.tools.checkstyle.DefaultConfiguration;
  import com.puppycrawl.tools.checkstyle.DetailAstImpl;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  public class MutableExceptionCheckTest extends AbstractModuleTestSupport {
  
      @Override
      protected String getPackageLocation() {
          return "com/puppycrawl/tools/checkstyle/checks/design/mutableexception";
      }
  
      @Test
      public void testClassExtendsGenericClass() throws Exception {
  
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
  
          verifyWithInlineConfigParser(
                  getPath("InputMutableExceptionClassExtendsGenericClass.java"),
                  expected);
      }
  
      @Test
      public void testDefault() throws Exception {
  
          final String[] expected = {
              "14:9: " + getCheckMessage(MSG_KEY, "errorCode"),
              "31:9: " + getCheckMessage(MSG_KEY, "errorCode"),
              "54:9: " + getCheckMessage(MSG_KEY, "errorCode"),
          };
  
          verifyWithInlineConfigParser(
                  getPath("InputMutableException.java"), expected);
      }
  
      @Test
      public void testMultipleInputs() throws Exception {
          final DefaultConfiguration checkConfig = createModuleConfig(MutableExceptionCheck.class);
          final String filePath1 = getPath("InputMutableException2.java");
          final String filePath2 = getPath("InputMutableExceptionMultipleInputs.java");
  
          final List<String> expected1 = Arrays.asList(
              "14:9: " + getCheckMessage(MSG_KEY, "errorCode"),
              "31:9: " + getCheckMessage(MSG_KEY, "errorCode"),
              "54:9: " + getCheckMessage(MSG_KEY, "errorCode"));
          final List<String> expected2 = Arrays.asList(
              "14:9: " + getCheckMessage(MSG_KEY, "errorCode"),
              "18:9: " + getCheckMessage(MSG_KEY, "errorCode"));
  
          final File[] inputs = {new File(filePath1), new File(filePath2)};
  
          verify(createChecker(checkConfig), inputs,
                  ImmutableMap.of(filePath1, expected1, filePath2, expected2));
      }
  
      @Test
      public void testFormat() throws Exception {
          final String[] expected = {
              "42:13: " + getCheckMessage(MSG_KEY, "errorCode"),
          };
  
          verifyWithInlineConfigParser(
                  getPath("InputMutableException3.java"), expected);
      }
  
      @Test
      public void testNested() throws Exception {
  
          final String[] expected = {
              "15:9: " + getCheckMessage(MSG_KEY, "code"),
          };
  
          verifyWithInlineConfigParser(
                  getPath("InputMutableExceptionNested.java"), expected);
      }
  
      @Test
      public void testGetAcceptableTokens() {
          final MutableExceptionCheck obj = new MutableExceptionCheck();
          final int[] expected = {TokenTypes.CLASS_DEF, TokenTypes.VARIABLE_DEF};
          assertWithMessage("Default acceptable tokens are invalid")
                  .that(obj.getAcceptableTokens())
                  .isEqualTo(expected);
      }
  
      @Test
      public void testGetRequiredTokens() {
          final MutableExceptionCheck obj = new MutableExceptionCheck();
          final int[] expected = {TokenTypes.CLASS_DEF, TokenTypes.VARIABLE_DEF};
          assertWithMessage("Default required tokens are invalid")
                  .that(obj.getRequiredTokens())
                  .isEqualTo(expected);
      }
  
      @Test
      public void testWrongTokenType() {
          final MutableExceptionCheck obj = new MutableExceptionCheck();
          final DetailAstImpl ast = new DetailAstImpl();
          ast.initialize(new CommonToken(TokenTypes.INTERFACE_DEF, "interface"));
          try {
              obj.visitToken(ast);
              assertWithMessage("IllegalStateException is expected")
                      .fail();
          }
          catch (IllegalStateException ex) {
              // exception is expected
              assertWithMessage("Invalid exception message")
                      .that(ex.getMessage())
                      .isEqualTo("interface[0x-1]");
          }
      }
  
  }
  