1 | /** |
---|
2 | * Licensed to the Apache Software Foundation (ASF) under one |
---|
3 | * or more contributor license agreements. See the NOTICE file |
---|
4 | * distributed with this work for additional information |
---|
5 | * regarding copyright ownership. The ASF licenses this file |
---|
6 | * to you under the Apache License, Version 2.0 (the |
---|
7 | * "License"); you may not use this file except in compliance |
---|
8 | * with the License. You may obtain a copy of the License at |
---|
9 | * |
---|
10 | * http://www.apache.org/licenses/LICENSE-2.0 |
---|
11 | * |
---|
12 | * Unless required by applicable law or agreed to in writing, software |
---|
13 | * distributed under the License is distributed on an "AS IS" BASIS, |
---|
14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
---|
15 | * See the License for the specific language governing permissions and |
---|
16 | * limitations under the License. |
---|
17 | */ |
---|
18 | |
---|
19 | package org.apache.hadoop.mapreduce; |
---|
20 | |
---|
21 | import java.io.DataInput; |
---|
22 | import java.io.DataOutput; |
---|
23 | import java.io.IOException; |
---|
24 | import java.text.NumberFormat; |
---|
25 | |
---|
26 | import org.apache.hadoop.io.Text; |
---|
27 | |
---|
28 | /** |
---|
29 | * JobID represents the immutable and unique identifier for |
---|
30 | * the job. JobID consists of two parts. First part |
---|
31 | * represents the jobtracker identifier, so that jobID to jobtracker map |
---|
32 | * is defined. For cluster setup this string is the jobtracker |
---|
33 | * start time, for local setting, it is "local". |
---|
34 | * Second part of the JobID is the job number. <br> |
---|
35 | * An example JobID is : |
---|
36 | * <code>job_200707121733_0003</code> , which represents the third job |
---|
37 | * running at the jobtracker started at <code>200707121733</code>. |
---|
38 | * <p> |
---|
39 | * Applications should never construct or parse JobID strings, but rather |
---|
40 | * use appropriate constructors or {@link #forName(String)} method. |
---|
41 | * |
---|
42 | * @see TaskID |
---|
43 | * @see TaskAttemptID |
---|
44 | * @see org.apache.hadoop.mapred.JobTracker#getNewJobId() |
---|
45 | * @see org.apache.hadoop.mapred.JobTracker#getStartTime() |
---|
46 | */ |
---|
47 | public class JobID extends org.apache.hadoop.mapred.ID |
---|
48 | implements Comparable<ID> { |
---|
49 | protected static final String JOB = "job"; |
---|
50 | private final Text jtIdentifier; |
---|
51 | |
---|
52 | protected static final NumberFormat idFormat = NumberFormat.getInstance(); |
---|
53 | static { |
---|
54 | idFormat.setGroupingUsed(false); |
---|
55 | idFormat.setMinimumIntegerDigits(4); |
---|
56 | } |
---|
57 | |
---|
58 | /** |
---|
59 | * Constructs a JobID object |
---|
60 | * @param jtIdentifier jobTracker identifier |
---|
61 | * @param id job number |
---|
62 | */ |
---|
63 | public JobID(String jtIdentifier, int id) { |
---|
64 | super(id); |
---|
65 | this.jtIdentifier = new Text(jtIdentifier); |
---|
66 | } |
---|
67 | |
---|
68 | public JobID() { |
---|
69 | jtIdentifier = new Text(); |
---|
70 | } |
---|
71 | |
---|
72 | public String getJtIdentifier() { |
---|
73 | return jtIdentifier.toString(); |
---|
74 | } |
---|
75 | |
---|
76 | @Override |
---|
77 | public boolean equals(Object o) { |
---|
78 | if (!super.equals(o)) |
---|
79 | return false; |
---|
80 | |
---|
81 | JobID that = (JobID)o; |
---|
82 | return this.jtIdentifier.equals(that.jtIdentifier); |
---|
83 | } |
---|
84 | |
---|
85 | /**Compare JobIds by first jtIdentifiers, then by job numbers*/ |
---|
86 | @Override |
---|
87 | public int compareTo(ID o) { |
---|
88 | JobID that = (JobID)o; |
---|
89 | int jtComp = this.jtIdentifier.compareTo(that.jtIdentifier); |
---|
90 | if(jtComp == 0) { |
---|
91 | return this.id - that.id; |
---|
92 | } |
---|
93 | else return jtComp; |
---|
94 | } |
---|
95 | |
---|
96 | /** |
---|
97 | * Add the stuff after the "job" prefix to the given builder. This is useful, |
---|
98 | * because the sub-ids use this substring at the start of their string. |
---|
99 | * @param builder the builder to append to |
---|
100 | * @return the builder that was passed in |
---|
101 | */ |
---|
102 | public StringBuilder appendTo(StringBuilder builder) { |
---|
103 | builder.append(SEPARATOR); |
---|
104 | builder.append(jtIdentifier); |
---|
105 | builder.append(SEPARATOR); |
---|
106 | builder.append(idFormat.format(id)); |
---|
107 | return builder; |
---|
108 | } |
---|
109 | |
---|
110 | @Override |
---|
111 | public int hashCode() { |
---|
112 | return jtIdentifier.hashCode() + id; |
---|
113 | } |
---|
114 | |
---|
115 | @Override |
---|
116 | public String toString() { |
---|
117 | return appendTo(new StringBuilder(JOB)).toString(); |
---|
118 | } |
---|
119 | |
---|
120 | @Override |
---|
121 | public void readFields(DataInput in) throws IOException { |
---|
122 | super.readFields(in); |
---|
123 | this.jtIdentifier.readFields(in); |
---|
124 | } |
---|
125 | |
---|
126 | @Override |
---|
127 | public void write(DataOutput out) throws IOException { |
---|
128 | super.write(out); |
---|
129 | jtIdentifier.write(out); |
---|
130 | } |
---|
131 | |
---|
132 | /** Construct a JobId object from given string |
---|
133 | * @return constructed JobId object or null if the given String is null |
---|
134 | * @throws IllegalArgumentException if the given string is malformed |
---|
135 | */ |
---|
136 | public static JobID forName(String str) throws IllegalArgumentException { |
---|
137 | if(str == null) |
---|
138 | return null; |
---|
139 | try { |
---|
140 | String[] parts = str.split("_"); |
---|
141 | if(parts.length == 3) { |
---|
142 | if(parts[0].equals(JOB)) { |
---|
143 | return new org.apache.hadoop.mapred.JobID(parts[1], |
---|
144 | Integer.parseInt(parts[2])); |
---|
145 | } |
---|
146 | } |
---|
147 | }catch (Exception ex) {//fall below |
---|
148 | } |
---|
149 | throw new IllegalArgumentException("JobId string : " + str |
---|
150 | + " is not properly formed"); |
---|
151 | } |
---|
152 | |
---|
153 | } |
---|