001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018 019 package org.apache.hadoop.mapred; 020 021 import java.io.DataInput; 022 import java.io.IOException; 023 024 import org.apache.hadoop.classification.InterfaceAudience; 025 import org.apache.hadoop.classification.InterfaceStability; 026 import org.apache.hadoop.mapreduce.TaskType; 027 028 /** 029 * TaskAttemptID represents the immutable and unique identifier for 030 * a task attempt. Each task attempt is one particular instance of a Map or 031 * Reduce Task identified by its TaskID. 032 * 033 * TaskAttemptID consists of 2 parts. First part is the 034 * {@link TaskID}, that this TaskAttemptID belongs to. 035 * Second part is the task attempt number. <br> 036 * An example TaskAttemptID is : 037 * <code>attempt_200707121733_0003_m_000005_0</code> , which represents the 038 * zeroth task attempt for the fifth map task in the third job 039 * running at the jobtracker started at <code>200707121733</code>. 040 * <p> 041 * Applications should never construct or parse TaskAttemptID strings 042 * , but rather use appropriate constructors or {@link #forName(String)} 043 * method. 044 * 045 * @see JobID 046 * @see TaskID 047 */ 048 @InterfaceAudience.Public 049 @InterfaceStability.Stable 050 public class TaskAttemptID extends org.apache.hadoop.mapreduce.TaskAttemptID { 051 052 /** 053 * Constructs a TaskAttemptID object from given {@link TaskID}. 054 * @param taskId TaskID that this task belongs to 055 * @param id the task attempt number 056 */ 057 public TaskAttemptID(TaskID taskId, int id) { 058 super(taskId, id); 059 } 060 061 /** 062 * Constructs a TaskId object from given parts. 063 * @param jtIdentifier jobTracker identifier 064 * @param jobId job number 065 * @param isMap whether the tip is a map 066 * @param taskId taskId number 067 * @param id the task attempt number 068 * @deprecated Use {@link #TaskAttemptID(String, int, TaskType, int, int)}. 069 */ 070 @Deprecated 071 public TaskAttemptID(String jtIdentifier, int jobId, boolean isMap, 072 int taskId, int id) { 073 this(jtIdentifier, jobId, isMap ? TaskType.MAP : TaskType.REDUCE, taskId, 074 id); 075 } 076 077 /** 078 * Constructs a TaskId object from given parts. 079 * @param jtIdentifier jobTracker identifier 080 * @param jobId job number 081 * @param type the TaskType 082 * @param taskId taskId number 083 * @param id the task attempt number 084 */ 085 public TaskAttemptID(String jtIdentifier, int jobId, TaskType type, 086 int taskId, int id) { 087 this(new TaskID(jtIdentifier, jobId, type, taskId), id); 088 } 089 090 public TaskAttemptID() { 091 super(new TaskID(), 0); 092 } 093 094 /** 095 * Downgrade a new TaskAttemptID to an old one 096 * @param old the new id 097 * @return either old or a new TaskAttemptID constructed to match old 098 */ 099 public static 100 TaskAttemptID downgrade(org.apache.hadoop.mapreduce.TaskAttemptID old) { 101 if (old instanceof TaskAttemptID) { 102 return (TaskAttemptID) old; 103 } else { 104 return new TaskAttemptID(TaskID.downgrade(old.getTaskID()), old.getId()); 105 } 106 } 107 108 public TaskID getTaskID() { 109 return (TaskID) super.getTaskID(); 110 } 111 112 public JobID getJobID() { 113 return (JobID) super.getJobID(); 114 } 115 116 @Deprecated 117 public static TaskAttemptID read(DataInput in) throws IOException { 118 TaskAttemptID taskId = new TaskAttemptID(); 119 taskId.readFields(in); 120 return taskId; 121 } 122 123 /** Construct a TaskAttemptID object from given string 124 * @return constructed TaskAttemptID object or null if the given String is null 125 * @throws IllegalArgumentException if the given string is malformed 126 */ 127 public static TaskAttemptID forName(String str 128 ) throws IllegalArgumentException { 129 return (TaskAttemptID) 130 org.apache.hadoop.mapreduce.TaskAttemptID.forName(str); 131 } 132 133 /** 134 * Returns a regex pattern which matches task attempt IDs. Arguments can 135 * be given null, in which case that part of the regex will be generic. 136 * For example to obtain a regex matching <i>all task attempt IDs</i> 137 * of <i>any jobtracker</i>, in <i>any job</i>, of the <i>first 138 * map task</i>, we would use : 139 * <pre> 140 * TaskAttemptID.getTaskAttemptIDsPattern(null, null, true, 1, null); 141 * </pre> 142 * which will return : 143 * <pre> "attempt_[^_]*_[0-9]*_m_000001_[0-9]*" </pre> 144 * @param jtIdentifier jobTracker identifier, or null 145 * @param jobId job number, or null 146 * @param isMap whether the tip is a map, or null 147 * @param taskId taskId number, or null 148 * @param attemptId the task attempt number, or null 149 * @return a regex pattern matching TaskAttemptIDs 150 */ 151 @Deprecated 152 public static String getTaskAttemptIDsPattern(String jtIdentifier, 153 Integer jobId, Boolean isMap, Integer taskId, Integer attemptId) { 154 return getTaskAttemptIDsPattern(jtIdentifier, jobId, 155 isMap ? TaskType.MAP : TaskType.REDUCE, taskId, attemptId); 156 } 157 158 /** 159 * Returns a regex pattern which matches task attempt IDs. Arguments can 160 * be given null, in which case that part of the regex will be generic. 161 * For example to obtain a regex matching <i>all task attempt IDs</i> 162 * of <i>any jobtracker</i>, in <i>any job</i>, of the <i>first 163 * map task</i>, we would use : 164 * <pre> 165 * TaskAttemptID.getTaskAttemptIDsPattern(null, null, TaskType.MAP, 1, null); 166 * </pre> 167 * which will return : 168 * <pre> "attempt_[^_]*_[0-9]*_m_000001_[0-9]*" </pre> 169 * @param jtIdentifier jobTracker identifier, or null 170 * @param jobId job number, or null 171 * @param type the {@link TaskType} 172 * @param taskId taskId number, or null 173 * @param attemptId the task attempt number, or null 174 * @return a regex pattern matching TaskAttemptIDs 175 */ 176 @Deprecated 177 public static String getTaskAttemptIDsPattern(String jtIdentifier, 178 Integer jobId, TaskType type, Integer taskId, Integer attemptId) { 179 StringBuilder builder = new StringBuilder(ATTEMPT).append(SEPARATOR); 180 builder.append(getTaskAttemptIDsPatternWOPrefix(jtIdentifier, jobId, 181 type, taskId, attemptId)); 182 return builder.toString(); 183 } 184 185 @Deprecated 186 static StringBuilder getTaskAttemptIDsPatternWOPrefix(String jtIdentifier 187 , Integer jobId, TaskType type, Integer taskId, Integer attemptId) { 188 StringBuilder builder = new StringBuilder(); 189 builder.append(TaskID.getTaskIDsPatternWOPrefix(jtIdentifier 190 , jobId, type, taskId)) 191 .append(SEPARATOR) 192 .append(attemptId != null ? attemptId : "[0-9]*"); 193 return builder; 194 } 195 }