contrib/src/main/java/org/apache/apex/malhar/contrib/zmq/AbstractSinglePortZeroMQOutputOperator.java

/**
 * 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.apex.malhar.contrib.zmq;

import com.datatorrent.api.DefaultInputPort;

/**
 * This is the base implementation of a single port ZeroMQ output adapter. 
 * This operator will behave like a publisher that replies to requests. 
 * Subclasses should implement the methods which create ZeroMQ messages from tuples.
 * <p>
 * <br>
 * Ports:<br>
 * <b>Input</b>: Can have one input port<br>
 * <b>Output</b>: no output port<br>
 * <br>
 * Properties:<br>
 * None<br>
 * <br>
 * Compile time checks:<br>
 * None<br>
 * <br>
 * Run time checks:<br>
 * None<br>
 * <br>
 * <b>Benchmarks</b>: Blast as many tuples as possible in inline mode<br>
 * <table border="1" cellspacing=1 cellpadding=1 summary="Benchmark table for AbstractSinglePortZeroMQOutputOperator&lt;K,V extends Number&gt; operator template">
 * <tr><th>In-Bound</th><th>Out-bound</th><th>Comments</th></tr>
 * <tr><td>One tuple per key per window per port</td><td><b>400 thousand K,V pairs/s</td><td>Out-bound rate is the main determinant of performance. Operator can process about 400 thousand unique (k,v immutable pairs) tuples/sec as ZeroMQ DAG. Tuples are assumed to be
 * immutable. If you use mutable tuples and have lots of keys, the benchmarks may differ</td></tr>
 * </table><br>
 * <br>
 * </p>
 * @displayName Abstract Single Port ZeroMQ Output
 * @category Messaging
 * @tags output operator
 * @since 0.3.2
 */
public abstract class AbstractSinglePortZeroMQOutputOperator<T> extends AbstractBaseZeroMQOutputOperator
{

  /**
   * Users need to provide conversion of Tuple to message
   * @param tuple
   */
  public abstract void processTuple(T tuple);

  /**
   * This is the input port which provides the tuples that are written out to ZeroMQ.
   */
  public final transient DefaultInputPort<T> inputPort = new DefaultInputPort<T>()
  {
    @Override
    public void process(T tuple)
    {
      processTuple(tuple); // This is an abstract call
    }
  };
}