org.apache.hadoop.mapred.TaskCompletionEvent.java Source code

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Here is the source code for org.apache.hadoop.mapred.TaskCompletionEvent.java

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/**
 * 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 org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceAudience.Private;
import org.apache.hadoop.classification.InterfaceStability;

/**
 * This is used to track task completion events on 
 * job tracker. 
 */
@InterfaceAudience.Public
@InterfaceStability.Stable
public class TaskCompletionEvent extends org.apache.hadoop.mapreduce.TaskCompletionEvent {
    @InterfaceAudience.Public
    @InterfaceStability.Stable
    /**
     *  Task Completion Statuses
     */
    static public enum Status {
        /**
         * Task Event Attempt failed but there are attempts remaining.
         */
        FAILED,
        /**
         * Task Event was killed.
         */
        KILLED,
        /**
         * Task Event was successful.
         */
        SUCCEEDED,
        /**
         * Used to Override a previously successful event status.
         * Example:  Map attempt runs and a SUCCEEDED event is sent. Later a task
         * is retroactively failed due to excessive fetch failure during shuffle
         * phase. When the retroactive attempt failure occurs, an OBSOLETE event is
         * sent for the map attempt indicating the prior event is no longer valid.
         */
        OBSOLETE,
        /**
         * Task Event attempt failed and no further attempts exist.
         * reached MAX attempts. When a reducer receives a TIPFAILED event it
         * gives up trying to shuffle data from that map task.
         */
        TIPFAILED
    }

    public static final TaskCompletionEvent[] EMPTY_ARRAY = new TaskCompletionEvent[0];

    /**
     * Default constructor for Writable.
     *
     */
    public TaskCompletionEvent() {
        super();
    }

    /**
     * Constructor. eventId should be created externally and incremented
     * per event for each job. 
     * @param eventId event id, event id should be unique and assigned in
     *  incrementally, starting from 0. 
     * @param taskId task id
     * @param status task's status 
     * @param taskTrackerHttp task tracker's host:port for http. 
     */
    public TaskCompletionEvent(int eventId, TaskAttemptID taskId, int idWithinJob, boolean isMap, Status status,
            String taskTrackerHttp) {
        super(eventId, taskId, idWithinJob, isMap,
                org.apache.hadoop.mapreduce.TaskCompletionEvent.Status.valueOf(status.name()), taskTrackerHttp);
    }

    @Private
    public static TaskCompletionEvent downgrade(org.apache.hadoop.mapreduce.TaskCompletionEvent event) {
        return new TaskCompletionEvent(event.getEventId(), TaskAttemptID.downgrade(event.getTaskAttemptId()),
                event.idWithinJob(), event.isMapTask(), Status.valueOf(event.getStatus().name()),
                event.getTaskTrackerHttp());
    }

    /**
     * Returns task id. 
     * @return task id
     * @deprecated use {@link #getTaskAttemptId()} instead.
     */
    @Deprecated
    public String getTaskId() {
        return getTaskAttemptId().toString();
    }

    /**
     * Returns task id. 
     * @return task id
     */
    public TaskAttemptID getTaskAttemptId() {
        return TaskAttemptID.downgrade(super.getTaskAttemptId());
    }

    /**
     * Returns {@link Status}
     * @return task completion status
     */
    public Status getTaskStatus() {
        return Status.valueOf(super.getStatus().name());
    }

    /**
     * Sets task id. 
     * @param taskId
     * @deprecated use {@link #setTaskAttemptId(TaskAttemptID)} instead.
     */
    @Deprecated
    public void setTaskId(String taskId) {
        this.setTaskAttemptId(TaskAttemptID.forName(taskId));
    }

    /**
     * Sets task id.
     * @param taskId
     * @deprecated use {@link #setTaskAttemptId(TaskAttemptID)} instead.
     */
    @Deprecated
    public void setTaskID(TaskAttemptID taskId) {
        this.setTaskAttemptId(taskId);
    }

    /**
     * Sets task id. 
     * @param taskId
     */
    protected void setTaskAttemptId(TaskAttemptID taskId) {
        super.setTaskAttemptId(taskId);
    }

    /**
     * Set task status. 
     * @param status
     */
    @Private
    public void setTaskStatus(Status status) {
        super.setTaskStatus(org.apache.hadoop.mapreduce.TaskCompletionEvent.Status.valueOf(status.name()));
    }

    /**
     * Set the task completion time
     * @param taskCompletionTime time (in millisec) the task took to complete
     */
    @Private
    public void setTaskRunTime(int taskCompletionTime) {
        super.setTaskRunTime(taskCompletionTime);
    }

    /**
     * set event Id. should be assigned incrementally starting from 0. 
     * @param eventId
     */
    @Private
    public void setEventId(int eventId) {
        super.setEventId(eventId);
    }

    /**
     * Set task tracker http location. 
     * @param taskTrackerHttp
     */
    @Private
    public void setTaskTrackerHttp(String taskTrackerHttp) {
        super.setTaskTrackerHttp(taskTrackerHttp);
    }
}