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;
  
  import org.apache.kafka.common.TopicPartition;
  import org.apache.kafka.streams.processor.TaskId;
  
  import java.util.Map;
  import java.util.Optional;
  import java.util.Set;
  
  
  /**
   * Metadata of a task.
   */
  public interface TaskMetadata {
  
      /**
       * Task ID of the task.
       *
       * @return task ID consisting of subtopology and partition ID
       */
      TaskId taskId();
  
      /**
       * Source topic partitions of the task.
       *
       * @return source topic partitions
       */
      Set<TopicPartition> topicPartitions();
  
      /**
       * Offsets of the source topic partitions committed so far by the task.
       *
       * @return map from source topic partitions to committed offsets
       */
      Map<TopicPartition, Long> committedOffsets();
  
      /**
       * End offsets of the source topic partitions of the task.
       *
       * @return map source topic partition to end offsets
       */
      Map<TopicPartition, Long> endOffsets();
  
      /**
       * Time task idling started. If the task is not currently idling it will return empty.
       *
       * @return time when task idling started, empty {@code Optional} if the task is currently not idling
       */
      Optional<Long> timeCurrentIdlingStarted();
  
      /**
       * Compares the specified object with this TaskMetadata. Returns {@code true} if and only if the specified object is
       * also a TaskMetadata and both {@code taskId()} and {@code topicPartitions()} are equal.
       *
       * @return {@code true} if this object is the same as the obj argument; {@code false} otherwise.
       */
      boolean equals(final Object o);
  
      /**
       * Returns the hash code value for this TaskMetadata. The hash code of a list is defined to be the result of the following calculation:
       * <pre>
       * {@code
       * Objects.hash(taskId(), topicPartitions());
       * }
       * </pre>
       *
       * @return a hash code value for this object.
       */
      int hashCode();
  
  }
  