core/src/main/java/org/apache/hama/bsp/TaskCompletionEvent.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.hama.bsp;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableUtils;

public class TaskCompletionEvent implements Writable {
  static public enum Status {
    FAILED, KILLED, SUCCEEDED, OBSOLETE, TIPFAILED
  }

  private int eventId;
  private String groomServerInfo;
  private int taskRunTime; // using int since runtime is the time difference
  private TaskAttemptID taskId;
  Status status;
  private int idWithinJob;
  public static final TaskCompletionEvent[] EMPTY_ARRAY = new TaskCompletionEvent[0];

  /**
   * Default constructor for Writable.
   * 
   */
  public TaskCompletionEvent() {
    taskId = new TaskAttemptID();
  }

  /**
   * 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, Status status, String groomServerInfo) {

    this.taskId = taskId;
    this.idWithinJob = idWithinJob;
    this.eventId = eventId;
    this.status = status;
    this.groomServerInfo = groomServerInfo;
  }

  /**
   * Returns event Id.
   * 
   * @return event id
   */
  public int getEventId() {
    return eventId;
  }

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

  /**
   * Returns enum Status.SUCESS or Status.FAILURE.
   * 
   * @return task tracker status
   */
  public Status getTaskStatus() {
    return status;
  }

  /**
   * http location of the groomserver where this task ran.
   * 
   * @return http location of groomserver tasklogs
   */
  public String getGroomServerInfo() {
    return groomServerInfo;
  }

  /**
   * Returns time (in millisec) the task took to complete.
   */
  public int getTaskRunTime() {
    return taskRunTime;
  }

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

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

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

  /**
   * Sets task id.
   * 
   * @param taskId
   */
  public void setTaskID(TaskAttemptID taskId) {
    this.taskId = taskId;
  }

  /**
   * Set task status.
   * 
   * @param status
   */
  public void setTaskStatus(Status status) {
    this.status = status;
  }

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

  @Override
  public String toString() {
    StringBuffer buf = new StringBuffer();
    buf.append("Task Id : ");
    buf.append(taskId);
    buf.append(", Status : ");
    buf.append(status.name());
    return buf.toString();
  }

  @Override
  public boolean equals(Object o) {
    if (o == null)
      return false;
    if (o.getClass().equals(TaskCompletionEvent.class)) {
      TaskCompletionEvent event = (TaskCompletionEvent) o;
      return this.eventId == event.getEventId()
          && this.idWithinJob == event.idWithinJob()
          && this.status.equals(event.getTaskStatus())
          && this.taskId.equals(event.getTaskAttemptId())
          && this.taskRunTime == event.getTaskRunTime()
          && this.groomServerInfo.equals(event.getGroomServerInfo());
    }
    return false;
  }

  @Override
  public int hashCode() {
    return toString().hashCode();
  }

  public int idWithinJob() {
    return idWithinJob;
  }

  // ////////////////////////////////////////////
  // Writable
  // ////////////////////////////////////////////
  @Override
  public void write(DataOutput out) throws IOException {
    taskId.write(out);
    WritableUtils.writeVInt(out, idWithinJob);
    WritableUtils.writeEnum(out, status);
    WritableUtils.writeString(out, groomServerInfo);
    WritableUtils.writeVInt(out, taskRunTime);
    WritableUtils.writeVInt(out, eventId);
  }

  @Override
  public void readFields(DataInput in) throws IOException {
    taskId.readFields(in);
    idWithinJob = WritableUtils.readVInt(in);
    status = WritableUtils.readEnum(in, Status.class);
    groomServerInfo = WritableUtils.readString(in);
    taskRunTime = WritableUtils.readVInt(in);
    eventId = WritableUtils.readVInt(in);
  }
}