| /** |
| * 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.mapreduce; |
| |
| import java.io.DataInput; |
| import java.io.DataOutput; |
| import java.io.IOException; |
| |
| /** |
| * TaskAttemptID represents the immutable and unique identifier for |
| * a task attempt. Each task attempt is one particular instance of a Map or |
| * Reduce Task identified by its TaskID. |
| * |
| * TaskAttemptID consists of 2 parts. First part is the |
| * {@link TaskID}, that this TaskAttemptID belongs to. |
| * Second part is the task attempt number. <br> |
| * An example TaskAttemptID is : |
| * <code>attempt_200707121733_0003_m_000005_0</code> , which represents the |
| * zeroth task attempt for the fifth map task in the third job |
| * running at the jobtracker started at <code>200707121733</code>. |
| * <p> |
| * Applications should never construct or parse TaskAttemptID strings |
| * , but rather use appropriate constructors or {@link #forName(String)} |
| * method. |
| * |
| * @see JobID |
| * @see TaskID |
| */ |
| public class TaskAttemptID extends org.apache.hadoop.mapred.ID { |
| protected static final String ATTEMPT = "attempt"; |
| private TaskID taskId; |
| |
| /** |
| * Constructs a TaskAttemptID object from given {@link TaskID}. |
| * @param taskId TaskID that this task belongs to |
| * @param id the task attempt number |
| */ |
| public TaskAttemptID(TaskID taskId, int id) { |
| super(id); |
| if(taskId == null) { |
| throw new IllegalArgumentException("taskId cannot be null"); |
| } |
| this.taskId = taskId; |
| } |
| |
| /** |
| * Constructs a TaskId object from given parts. |
| * @param jtIdentifier jobTracker identifier |
| * @param jobId job number |
| * @param type the TaskType |
| * @param taskId taskId number |
| * @param id the task attempt number |
| */ |
| public TaskAttemptID(String jtIdentifier, int jobId, TaskType type, |
| int taskId, int id) { |
| this(new TaskID(jtIdentifier, jobId, type, taskId), id); |
| } |
| |
| public TaskAttemptID() { |
| taskId = new TaskID(); |
| } |
| |
| /** Returns the {@link JobID} object that this task attempt belongs to */ |
| public JobID getJobID() { |
| return taskId.getJobID(); |
| } |
| |
| /** Returns the {@link TaskID} object that this task attempt belongs to */ |
| public TaskID getTaskID() { |
| return taskId; |
| } |
| |
| /**Returns the TaskType of the TaskAttemptID */ |
| public TaskType getTaskType() { |
| return taskId.getTaskType(); |
| } |
| @Override |
| public boolean equals(Object o) { |
| if (!super.equals(o)) |
| return false; |
| |
| TaskAttemptID that = (TaskAttemptID)o; |
| return this.taskId.equals(that.taskId); |
| } |
| |
| /** |
| * Add the unique string to the StringBuilder |
| * @param builder the builder to append ot |
| * @return the builder that was passed in. |
| */ |
| protected StringBuilder appendTo(StringBuilder builder) { |
| return taskId.appendTo(builder).append(SEPARATOR).append(id); |
| } |
| |
| @Override |
| public void readFields(DataInput in) throws IOException { |
| super.readFields(in); |
| taskId.readFields(in); |
| } |
| |
| @Override |
| public void write(DataOutput out) throws IOException { |
| super.write(out); |
| taskId.write(out); |
| } |
| |
| @Override |
| public int hashCode() { |
| return taskId.hashCode() * 5 + id; |
| } |
| |
| /**Compare TaskIds by first tipIds, then by task numbers. */ |
| @Override |
| public int compareTo(ID o) { |
| TaskAttemptID that = (TaskAttemptID)o; |
| int tipComp = this.taskId.compareTo(that.taskId); |
| if(tipComp == 0) { |
| return this.id - that.id; |
| } |
| else return tipComp; |
| } |
| @Override |
| public String toString() { |
| return appendTo(new StringBuilder(ATTEMPT)).toString(); |
| } |
| |
| /** Construct a TaskAttemptID object from given string |
| * @return constructed TaskAttemptID object or null if the given String is null |
| * @throws IllegalArgumentException if the given string is malformed |
| */ |
| public static TaskAttemptID forName(String str |
| ) throws IllegalArgumentException { |
| if(str == null) |
| return null; |
| try { |
| String[] parts = str.split(Character.toString(SEPARATOR)); |
| if(parts.length == 6) { |
| if(parts[0].equals(ATTEMPT)) { |
| String type = parts[3]; |
| TaskType t = TaskID.getTaskType(type.charAt(0)); |
| if(t != null) { |
| return new org.apache.hadoop.mapred.TaskAttemptID |
| (parts[1], |
| Integer.parseInt(parts[2]), |
| t, Integer.parseInt(parts[4]), |
| Integer.parseInt(parts[5])); |
| } else throw new Exception(); |
| } |
| } |
| } catch (Exception ex) { |
| //fall below |
| } |
| throw new IllegalArgumentException("TaskAttemptId string : " + str |
| + " is not properly formed"); |
| } |
| |
| } |