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.naming;
  
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  /**
   * <p>
   * Checks that type names conform to a specified pattern.
   * </p>
   * <ul>
   * <li>
   * Property {@code format} - Specifies valid identifiers.
   * Type is {@code java.util.regex.Pattern}.
   * Default value is {@code "^[A-Z][a-zA-Z0-9]*$"}.
   * </li>
   * <li>
   * Property {@code applyToPublic} - Controls whether to apply the check to public member.
   * Type is {@code boolean}.
   * Default value is {@code true}.
   * </li>
   * <li>
   * Property {@code applyToProtected} - Controls whether to apply the check to protected member.
   * Type is {@code boolean}.
   * Default value is {@code true}.
   * </li>
   * <li>
   * Property {@code applyToPackage} - Controls whether to apply the check to package-private member.
   * Type is {@code boolean}.
   * Default value is {@code true}.
   * </li>
   * <li>
   * Property {@code applyToPrivate} - Controls whether to apply the check to private member.
   * Type is {@code boolean}.
   * Default value is {@code true}.
   * </li>
   * <li>
   * Property {@code tokens} - tokens to check
   * Type is {@code java.lang.String[]}.
   * Validation type is {@code tokenSet}.
   * Default value is:
   * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#CLASS_DEF">
   * CLASS_DEF</a>,
   * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#INTERFACE_DEF">
   * INTERFACE_DEF</a>,
   * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ENUM_DEF">
   * ENUM_DEF</a>,
   * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ANNOTATION_DEF">
   * ANNOTATION_DEF</a>,
   * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#RECORD_DEF">
   * RECORD_DEF</a>.
   * </li>
   * </ul>
   * <p>
   * To configure the check:
   * </p>
   * <pre>
   * &lt;module name=&quot;TypeName&quot;/&gt;
   * </pre>
   * <p>Code Example:</p>
   * <pre>
   * public interface FirstName {} // OK
   * protected class SecondName {} // OK
   * enum Third_Name {} // violation, name 'Third_Name' must match pattern '^[A-Z][a-zA-Z0-9]*$'
   * private class FourthName_ {} // violation, name 'FourthName_'
   *                              // must match pattern '^[A-Z][a-zA-Z0-9]*$'
   * </pre>
   * <p>
   * An example of how to configure the check for names that begin with
   * a lower case letter, followed by letters, digits, and underscores.
   * Also, suppress the check from being applied to protected and private type:
   * </p>
   * <pre>
   * &lt;module name=&quot;TypeName&quot;&gt;
   *   &lt;property name=&quot;format&quot; value=&quot;^[a-z](_?[a-zA-Z0-9]+)*$&quot;/&gt;
   *   &lt;property name=&quot;applyToProtected&quot; value=&quot;false&quot;/&gt;
   *   &lt;property name=&quot;applyToPrivate&quot; value=&quot;false&quot;/&gt;
   * &lt;/module&gt;
   * </pre>
   * <p>Code Example:</p>
   * <pre>
   * public interface firstName {} // OK
   * public class SecondName {} // violation, name 'SecondName'
   *                            // must match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
   * protected class ThirdName {} // OK
   * private class FourthName {} // OK
   * </pre>
   * <p>
   * The following configuration element ensures that interface names begin with {@code "I_"},
   * followed by letters and digits:
   * </p>
   * <pre>
   * &lt;module name=&quot;TypeName&quot;&gt;
   *   &lt;property name=&quot;format&quot;
   *     value=&quot;^I_[a-zA-Z0-9]*$&quot;/&gt;
   *   &lt;property name=&quot;tokens&quot;
   *     value=&quot;INTERFACE_DEF&quot;/&gt;
   * &lt;/module&gt;
   * </pre>
   * <p>Code Example:</p>
   * <pre>
   * public interface I_firstName {} // OK
   * interface SecondName {} // violation, name 'SecondName'
   *                         // must match pattern '^I_[a-zA-Z0-9]*$'
   * </pre>
   * <p>
   * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
   * </p>
   * <p>
   * Violation Message Keys:
   * </p>
   * <ul>
   * <li>
   * {@code name.invalidPattern}
   * </li>
   * </ul>
   *
   * @since 3.0
   */
  public class TypeNameCheck
      extends AbstractAccessControlNameCheck {
  
      /**
       * Default pattern for type name.
       */
      public static final String DEFAULT_PATTERN = "^[A-Z][a-zA-Z0-9]*$";
  
      /**
       * Creates a new {@code TypeNameCheck} instance.
       */
      public TypeNameCheck() {
          super(DEFAULT_PATTERN);
      }
  
      @Override
      public int[] getDefaultTokens() {
          return getAcceptableTokens();
      }
  
      @Override
      public int[] getAcceptableTokens() {
          return new int[] {
              TokenTypes.CLASS_DEF,
              TokenTypes.INTERFACE_DEF,
              TokenTypes.ENUM_DEF,
              TokenTypes.ANNOTATION_DEF,
              TokenTypes.RECORD_DEF,
          };
      }
  
      @Override
      public int[] getRequiredTokens() {
          return CommonUtil.EMPTY_INT_ARRAY;
      }
  
  }
  