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 backtype.storm.transactional.partitioned;
  
  import backtype.storm.coordination.BatchOutputCollector;
  import backtype.storm.task.TopologyContext;
  import backtype.storm.topology.IComponent;
  import backtype.storm.transactional.TransactionAttempt;
  import java.util.Map;
  
  /**
   * This defines a transactional spout which does NOT necessarily replay the same batch every time
   * it emits a batch for a transaction id.
   */
  public interface IOpaquePartitionedTransactionalSpout<T> extends IComponent {
      interface Coordinator {
          /**
           * Returns true if its ok to emit start a new transaction, false otherwise (will skip this transaction).
           *
           * You should sleep here if you want a delay between asking for the next transaction (this will be called repeatedly in a loop).
           */
          boolean isReady();
  
          void close();
      }
  
      interface Emitter<X> {
          /**
           * Emit a batch of tuples for a partition/transaction.
           *
           * Return the metadata describing this batch that will be used as lastPartitionMeta for
           * defining the parameters of the next batch.
           */
          X emitPartitionBatch(TransactionAttempt tx, BatchOutputCollector collector, int partition, X lastPartitionMeta);
  
          int numPartitions();
  
          void close();
      }
  
      Emitter<T> getEmitter(Map conf, TopologyContext context);
  
      Coordinator getCoordinator(Map conf, TopologyContext context);
  }
  