| /** |
| * 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.hadoop.mapred; |
| |
| import java.io.DataInput; |
| import java.io.DataOutput; |
| import java.io.IOException; |
| |
| /** |
| * This class is used for notifying a SimulatorTaskTracker running a reduce task |
| * that all map tasks of the job are done. A SimulatorJobTracker notifies a |
| * SimulatorTaskTracker by sending this TaskTrackerAction in response to a |
| * heartbeat(). Represents a directive to start running the user code of the |
| * reduce task. |
| * |
| * We introduced this extra 'push' mechanism so that we don't have to implement |
| * the corresponding, more complicated 'pull' part of the InterTrackerProtocol. |
| * We do not use proper simulation Events for signaling, and hack heartbeat() |
| * instead, since the job tracker does not emit Events and does not know the |
| * recipient task tracker _Java_ object. |
| */ |
| class AllMapsCompletedTaskAction extends TaskTrackerAction { |
| /** Task attempt id of the reduce task that can proceed. */ |
| private final org.apache.hadoop.mapreduce.TaskAttemptID taskId; |
| |
| /** |
| * Constructs an AllMapsCompletedTaskAction object for a given |
| * {@link org.apache.hadoop.mapreduce.TaskAttemptID}. |
| * |
| * @param taskId |
| * {@link org.apache.hadoop.mapreduce.TaskAttemptID} of the reduce |
| * task that can proceed |
| */ |
| public AllMapsCompletedTaskAction( |
| org.apache.hadoop.mapreduce.TaskAttemptID taskId) { |
| super(ActionType.LAUNCH_TASK); |
| this.taskId = taskId; |
| } |
| |
| /** |
| * Get the task attempt id of the reduce task. |
| * |
| * @return the {@link org.apache.hadoop.mapreduce.TaskAttemptID} of the |
| * task-attempt. |
| */ |
| public org.apache.hadoop.mapreduce.TaskAttemptID getTaskID() { |
| return taskId; |
| } |
| |
| @Override |
| public void write(DataOutput out) throws IOException { |
| super.write(out); |
| taskId.write(out); |
| } |
| |
| @Override |
| public void readFields(DataInput in) throws IOException { |
| super.readFields(in); |
| taskId.readFields(in); |
| } |
| |
| @Override |
| public String toString() { |
| return "AllMapsCompletedTaskAction[taskID=" + taskId + "]"; |
| } |
| } |