core/src/main/java/org/apache/hama/bsp/RunningJob.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.IOException;

/**
 * <code>RunningJob</code> is the user-interface to query for details on a
 * running BSP job.
 * 
 * <p>
 * Clients can get hold of <code>RunningJob</code> via the {@link BSPJobClient}
 * and then query the running-job for details such as name, configuration,
 * progress etc.
 * </p>
 * 
 * @see BSPJobClient
 */
public interface RunningJob {
  /**
   * Get the job identifier.
   * 
   * @return the job identifier.
   */
  public BSPJobID getID();

  /**
   * Get the name of the job.
   * 
   * @return the name of the job.
   */
  public String getJobName();

  /**
   * Get the path of the submitted job configuration.
   * 
   * @return the path of the submitted job configuration.
   */
  public String getJobFile();

  public Counters getCounters();
  
  /**
   * Get the <i>progress</i> of the job's tasks, as a float between 0.0 and 1.0.
   * When all bsp tasks have completed, the function returns 1.0.
   * 
   * @return the progress of the job's tasks.
   * @throws IOException
   */
  public long progress() throws IOException;

  /**
   * Check if the job is finished or not. This is a non-blocking call.
   * 
   * @return <code>true</code> if the job is complete, else <code>false</code>.
   * @throws IOException
   */
  public boolean isComplete() throws IOException;

  /**
   * Check if the job completed successfully.
   * 
   * @return <code>true</code> if the job succeeded, else <code>false</code>.
   * @throws IOException
   */
  public boolean isSuccessful() throws IOException;

  /**
   * Blocks until the job is complete.
   * 
   * @throws IOException
   */
  public void waitForCompletion() throws IOException;

  /**
   * Returns the current state of the Job. {@link JobStatus}
   * 
   * @throws IOException
   */
  public int getJobState() throws IOException;

  /**
   * Kill the running job. Blocks until all job tasks have been killed as well.
   * If the job is no longer running, it simply returns.
   * 
   * @throws IOException
   */
  public void killJob() throws IOException;

  /**
   * Kill indicated task attempt.
   * 
   * @param taskId the id of the task to be terminated.
   * @param shouldFail if true the task is failed and added to failed tasks
   *          list, otherwise it is just killed, w/o affecting job failure
   *          status.
   * @throws IOException
   */
  public void killTask(TaskAttemptID taskId, boolean shouldFail)
      throws IOException;

  public long getSuperstepCount() throws IOException;

  /**
   * @return the latest status of the job.
   */
  public JobStatus getStatus();

  public TaskCompletionEvent[] getTaskCompletionEvents(int eventCounter);
}