/*
 * Copyright (c) 2013 DataTorrent, Inc. ALL Rights Reserved.
 *
 * Licensed 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 com.datatorrent.lib.db;

import java.util.Collection;
import com.google.common.collect.Lists;

/**
 * This is the base implementation for an aggregate output operator,
 * which writes to a transactionable store.&nbsp;
 * All the writes to the store over an application window are sent in one batch.
 * <p></p>
 * @displayName Abstract Batch Transactionable Store Output
 * @category Store
 * @tags transactional, output operator
 *
 * @param <T> The tuple type.
 * @param <S> The store type.
 * @since 1.0.2
 */
public abstract class AbstractBatchTransactionableStoreOutputOperator<T, S extends TransactionableStore> extends AbstractAggregateTransactionableStoreOutputOperator<T, S> {

  private Collection<T> tuples;
  public AbstractBatchTransactionableStoreOutputOperator(){
    tuples = Lists.newArrayList();
  }

  @Override
  public void processTuple(T tuple)
  {
    tuples.add(tuple);
  }

  @Override
  public void endWindow()
  {
    super.endWindow();
    tuples.clear();
  }

  /**
   * Processes the whole batch at the end window and writes to the store.
   *
   */
  public abstract void processBatch(Collection<T> tuples);

  @Override
  public void storeAggregate() {
    processBatch(tuples);
  }
}