trunk/core/src/main/scala/kafka/producer/async/EventHandler.scala

/**
 * 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 kafka.producer.async

import java.util.Properties
import kafka.producer.SyncProducer
import kafka.serializer.Encoder

/**
 * Handler that dispatches the batched data from the queue of the
 * asynchronous producer.
 */
trait EventHandler[T] {
  /**
   * Initializes the event handler using a Properties object
   * @param props the properties used to initialize the event handler
  */
  def init(props: Properties) {}

  /**
   * Callback to dispatch the batched data and send it to a Kafka server
   * @param events the data sent to the producer
   * @param producer the low-level producer used to send the data
  */
  def handle(events: Seq[QueueItem[T]], producer: SyncProducer, encoder: Encoder[T])

  /**
   * Cleans up and shuts down the event handler
  */
  def close {}
}