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.streams.state.internals;
  
  import org.apache.kafka.common.TopicPartition;
  import org.apache.kafka.streams.KafkaStreams;
  import org.apache.kafka.streams.StreamsMetadata;
  import org.apache.kafka.streams.state.HostInfo;
  
  import java.util.Collections;
  import java.util.Objects;
  import java.util.Set;
  
  /**
   * Represents the state of an instance (process) in a {@link KafkaStreams} application.
   * It contains the user supplied {@link HostInfo} that can be used by developers to build
   * APIs and services to connect to other instances, the Set of state stores available on
   * the instance and the Set of {@link TopicPartition}s available on the instance.
   * NOTE: This is a point in time view. It may change when rebalances happen.
   */
  public class StreamsMetadataImpl implements StreamsMetadata {
  
      private final HostInfo hostInfo;
  
      private final Set<String> stateStoreNames;
  
      private final Set<TopicPartition> topicPartitions;
  
      private final Set<String> standbyStateStoreNames;
  
      private final Set<TopicPartition> standbyTopicPartitions;
  
      private final String topologyName;
  
      public StreamsMetadataImpl(final HostInfo hostInfo,
                                 final Set<String> stateStoreNames,
                                 final Set<TopicPartition> topicPartitions,
                                 final Set<String> standbyStoreNames,
                                 final Set<TopicPartition> standbyTopicPartitions) {
          this(
              hostInfo,
              stateStoreNames,
              topicPartitions,
              standbyStoreNames,
              standbyTopicPartitions,
              null
          );
      }
  
      public StreamsMetadataImpl(final HostInfo hostInfo,
                                 final Set<String> stateStoreNames,
                                 final Set<TopicPartition> topicPartitions,
                                 final Set<String> standbyStoreNames,
                                 final Set<TopicPartition> standbyTopicPartitions,
                                 final String topologyName) {
          this.hostInfo = hostInfo;
          this.stateStoreNames = Collections.unmodifiableSet(stateStoreNames);
          this.topicPartitions = Collections.unmodifiableSet(topicPartitions);
          this.standbyTopicPartitions = Collections.unmodifiableSet(standbyTopicPartitions);
          this.standbyStateStoreNames = Collections.unmodifiableSet(standbyStoreNames);
          this.topologyName = topologyName;
      }
  
      /**
       * The value of {@link org.apache.kafka.streams.StreamsConfig#APPLICATION_SERVER_CONFIG} configured for the streams
       * instance, which is typically host/port
       *
       * @return {@link HostInfo} corresponding to the streams instance
       */
      @Override
      public HostInfo hostInfo() {
          return hostInfo;
      }
  
      /**
       * State stores owned by the instance as an active replica
       *
       * @return set of active state store names
       */
      @Override
      public Set<String> stateStoreNames() {
          return stateStoreNames;
      }
  
      /**
       * Topic partitions consumed by the instance as an active replica
       *
       * @return set of active topic partitions
       */
      @Override
      public Set<TopicPartition> topicPartitions() {
          return topicPartitions;
      }
  
      /**
       * (Source) Topic partitions for which the instance acts as standby.
       *
       * @return set of standby topic partitions
       */
      @Override
      public Set<TopicPartition> standbyTopicPartitions() {
          return standbyTopicPartitions;
      }
  
      /**
       * State stores owned by the instance as a standby replica
       *
       * @return set of standby state store names
       */
      @Override
      public Set<String> standbyStateStoreNames() {
          return standbyStateStoreNames;
      }
  
      @Override
      public String host() {
          return hostInfo.host();
      }
  
      @SuppressWarnings("unused")
      @Override
      public int port() {
          return hostInfo.port();
      }
  
      public String topologyName() {
          return topologyName;
      }
  
      @Override
      public boolean equals(final Object o) {
          if (this == o) {
              return true;
          }
          if (o == null || getClass() != o.getClass()) {
              return false;
          }
  
          final StreamsMetadataImpl that = (StreamsMetadataImpl) o;
          return Objects.equals(hostInfo, that.hostInfo)
              && Objects.equals(stateStoreNames, that.stateStoreNames)
              && Objects.equals(topicPartitions, that.topicPartitions)
              && Objects.equals(standbyStateStoreNames, that.standbyStateStoreNames)
              && Objects.equals(standbyTopicPartitions, that.standbyTopicPartitions)
              && Objects.equals(topologyName, that.topologyName);
      }
  
      @Override
      public int hashCode() {
          return Objects.hash(hostInfo, stateStoreNames, topicPartitions, standbyStateStoreNames, standbyTopicPartitions);
      }
  
      @Override
      public String toString() {
          final String str =
              "StreamsMetadata {" +
                  "hostInfo=" + hostInfo +
                  ", stateStoreNames=" + stateStoreNames +
                  ", topicPartitions=" + topicPartitions +
                  ", standbyStateStoreNames=" + standbyStateStoreNames +
                  ", standbyTopicPartitions=" + standbyTopicPartitions;
          if (topologyName == null) {
              return str + '}';
          } else {
              return str +
                  ", topologyName=" + topologyName +
                  '}';
          }
      }
  }
  