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.consumer.internals;
  
  import org.apache.kafka.common.TopicPartition;
  
  /**
   * {@code FetchUtils} provides a place for disparate parts of the fetch logic to live.
   */
  public class FetchUtils {
  
      /**
       * Performs two combined actions based on the state related to the {@link TopicPartition}:
       *
       * <ol>
       *     <li>
       *         Invokes {@link ConsumerMetadata#requestUpdate(boolean)} to signal that the metadata is incorrect and
       *         needs to be updated
       *     </li>
       *     <li>
       *         Invokes {@link SubscriptionState#clearPreferredReadReplica(TopicPartition)} to clear out any read replica
       *         information that may be present.
       *     </li>
       * </ol>
       *
       * This utility method should be invoked if the client detects (or is told by a node in the broker) that an
       * attempt was made to fetch from a node that isn't the leader or preferred replica.
       *
       * @param metadata {@link ConsumerMetadata} for which to request an update
       * @param subscriptions {@link SubscriptionState} to clear any internal read replica node
       * @param topicPartition {@link TopicPartition} for which this state change is related
       */
      static void requestMetadataUpdate(final ConsumerMetadata metadata,
                                        final SubscriptionState subscriptions,
                                        final TopicPartition topicPartition) {
          metadata.requestUpdate(false);
          subscriptions.clearPreferredReadReplica(topicPartition);
      }
  }
  