content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.kafka.common;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  
  /**
   * A class used to represent a collection of topics. This collection may define topics by name or ID.
   */
  public abstract class TopicCollection {
  
      private TopicCollection() {}
  
      /**
       * @return a collection of topics defined by topic ID
       */
      public static TopicIdCollection ofTopicIds(Collection<Uuid> topics) {
          return new TopicIdCollection(topics);
      }
  
      /**
       * @return a collection of topics defined by topic name
       */
      public static TopicNameCollection ofTopicNames(Collection<String> topics) {
          return new TopicNameCollection(topics);
      }
  
      /**
       * A class used to represent a collection of topics defined by their topic ID.
       * Subclassing this class beyond the classes provided here is not supported.
       */
      public static class TopicIdCollection extends TopicCollection {
          private final Collection<Uuid> topicIds;
  
          private TopicIdCollection(Collection<Uuid> topicIds) {
              this.topicIds = new ArrayList<>(topicIds);
          }
  
          /**
           * @return A collection of topic IDs
           */
          public Collection<Uuid> topicIds() {
              return Collections.unmodifiableCollection(topicIds);
          }
      }
  
      /**
       * A class used to represent a collection of topics defined by their topic name.
       * Subclassing this class beyond the classes provided here is not supported.
       */
      public static class TopicNameCollection extends TopicCollection {
          private final Collection<String> topicNames;
  
          private TopicNameCollection(Collection<String> topicNames) {
              this.topicNames = new ArrayList<>(topicNames);
          }
  
          /**
           * @return A collection of topic names
           */
          public Collection<String> topicNames() {
              return Collections.unmodifiableCollection(topicNames);
          }
      }
  }
  