content: /**
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.aurora.scheduler.base;
  
  import java.util.regex.Pattern;
  
  import javax.annotation.Nullable;
  
  import static org.apache.aurora.gen.apiConstants.GOOD_IDENTIFIER_PATTERN_JVM;
  
  /**
   * Utility class for validation of strings provided by end-users.
   */
  public final class UserProvidedStrings {
    private static final Pattern GOOD_IDENTIFIER = Pattern.compile(GOOD_IDENTIFIER_PATTERN_JVM);
    private static final int MAX_IDENTIFIER_LENGTH = 255;
  
    private UserProvidedStrings() {
      // Utility class.
    }
  
    /**
     * Verifies that an identifier is an acceptable name component.
     *
     * @param identifier Identifier to check.
     * @return false if the identifier is null or invalid.
     */
    public static boolean isGoodIdentifier(@Nullable String identifier) {
      return identifier != null
          && GOOD_IDENTIFIER.matcher(identifier).matches()
          && identifier.length() <= MAX_IDENTIFIER_LENGTH;
    }
  }
  