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.clients;
  
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * Maintains node api versions for access outside of NetworkClient (which is where the information is derived).
   * The pattern is akin to the use of {@link Metadata} for topic metadata.
   *
   * NOTE: This class is intended for INTERNAL usage only within Kafka.
   */
  public class ApiVersions {
  
      private final Map<String, NodeApiVersions> nodeApiVersions = new HashMap<>();
  
      // The maximum finalized feature epoch of all the node api versions.
      private long maxFinalizedFeaturesEpoch = -1;
      private Map<String, Short> finalizedFeatures;
  
      public static class FinalizedFeaturesInfo {
          public final long finalizedFeaturesEpoch;
          public final Map<String, Short> finalizedFeatures;
          FinalizedFeaturesInfo(long finalizedFeaturesEpoch, Map<String, Short> finalizedFeatures) {
              this.finalizedFeaturesEpoch = finalizedFeaturesEpoch;
              this.finalizedFeatures = finalizedFeatures;
          }
      }
  
      public synchronized void update(String nodeId, NodeApiVersions nodeApiVersions) {
          this.nodeApiVersions.put(nodeId, nodeApiVersions);
          if (maxFinalizedFeaturesEpoch < nodeApiVersions.finalizedFeaturesEpoch()) {
              this.maxFinalizedFeaturesEpoch = nodeApiVersions.finalizedFeaturesEpoch();
              this.finalizedFeatures = nodeApiVersions.finalizedFeatures();
          }
      }
  
      public synchronized void remove(String nodeId) {
          this.nodeApiVersions.remove(nodeId);
      }
  
      public synchronized NodeApiVersions get(String nodeId) {
          return this.nodeApiVersions.get(nodeId);
      }
  
      public synchronized long getMaxFinalizedFeaturesEpoch() {
          return maxFinalizedFeaturesEpoch;
      }
  
      public synchronized FinalizedFeaturesInfo getFinalizedFeaturesInfo() {
          return new FinalizedFeaturesInfo(maxFinalizedFeaturesEpoch, finalizedFeatures);
      }
  
  }
  