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 static com.puppycrawl.tools.checkstyle.checks.coding.IllegalTokenCheck.MSG_KEY;
  
  import java.nio.charset.StandardCharsets;
  
  import org.junit.jupiter.api.Test;
  
  import com.puppycrawl.tools.checkstyle.AbstractModuleTestSupport;
  import com.puppycrawl.tools.checkstyle.internal.utils.CheckUtil;
  import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
  
  public class IllegalTokenCheckTest
      extends AbstractModuleTestSupport {
  
      @Override
      protected String getPackageLocation() {
          return "com/puppycrawl/tools/checkstyle/checks/coding/illegaltoken";
      }
  
      @Test
      public void testCheckWithDefaultSettings()
              throws Exception {
          final String[] expected = {
              "36:14: " + getCheckMessage(MSG_KEY, "label:"),
              "38:25: " + getCheckMessage(MSG_KEY, "anotherLabel:"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputIllegalTokens.java"), expected);
      }
  
      @Test
      public void testPreviouslyIllegalTokens()
              throws Exception {
          final String[] expected = {
              "18:9: " + getCheckMessage(MSG_KEY, "switch"),
              "21:18: " + getCheckMessage(MSG_KEY, "--"),
              "22:18: " + getCheckMessage(MSG_KEY, "++"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputIllegalTokens2.java"), expected);
      }
  
      @Test
      public void testNative() throws Exception {
          final String[] expected = {
              "27:12: " + getCheckMessage(MSG_KEY, "native"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputIllegalTokens3.java"), expected);
      }
  
      @Test
      public void testCommentContentToken()
              throws Exception {
  
          final String path = getPath("InputIllegalTokens4.java");
          final String lineSeparator =
                  CheckUtil.getLineSeparatorForFile(path, StandardCharsets.UTF_8);
          final String[] expected = {
              "1:3: " + getCheckMessage(MSG_KEY,
                          JavadocUtil.escapeAllControlChars(
                              " // violation\\n"
                              + "IllegalToken\\n" + "tokens = COMMENT_CONTENT"
                              + lineSeparator
                              + lineSeparator
                              + lineSeparator)),
              "10:3: " + getCheckMessage(MSG_KEY,
                          JavadocUtil.escapeAllControlChars(
                              "* // violation" + lineSeparator
                              + " * Test for illegal tokens"
                              + lineSeparator + " ")),
              "38:29: " + getCheckMessage(MSG_KEY,
                          JavadocUtil.escapeAllControlChars(
                              " some comment href // violation" + lineSeparator)),
              "42:28: " + getCheckMessage(MSG_KEY,
                          JavadocUtil.escapeAllControlChars(
                              " some a href // violation" + lineSeparator)),
          };
          verifyWithInlineConfigParser(path, expected);
      }
  
      @Test
      public void testBlockCommentBeginToken()
              throws Exception {
  
          final String[] expected = {
              "1:1: " + getCheckMessage(MSG_KEY, "/*"),
              "10:1: " + getCheckMessage(MSG_KEY, "/*"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputIllegalTokens5.java"), expected);
      }
  
      @Test
      public void testBlockCommentEndToken()
              throws Exception {
  
          final String[] expected = {
              "6:1: " + getCheckMessage(MSG_KEY, "*/"),
              "12:2: " + getCheckMessage(MSG_KEY, "*/"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputIllegalTokens6.java"), expected);
      }
  
      @Test
      public void testSingleLineCommentToken()
              throws Exception {
  
          final String[] expected = {
              "38:27: " + getCheckMessage(MSG_KEY, "//"),
              "42:26: " + getCheckMessage(MSG_KEY, "//"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputIllegalTokens7.java"), expected);
      }
  
  }
  