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    
027    /**
028     * JobID represents the immutable and unique identifier for 
029     * the job. JobID consists of two parts. First part 
030     * represents the jobtracker identifier, so that jobID to jobtracker map 
031     * is defined. For cluster setup this string is the jobtracker 
032     * start time, for local setting, it is "local".
033     * Second part of the JobID is the job number. <br> 
034     * An example JobID is : 
035     * <code>job_200707121733_0003</code> , which represents the third job 
036     * running at the jobtracker started at <code>200707121733</code>. 
037     * <p>
038     * Applications should never construct or parse JobID strings, but rather 
039     * use appropriate constructors or {@link #forName(String)} method. 
040     * 
041     * @see TaskID
042     * @see TaskAttemptID
043     */
044    @InterfaceAudience.Public
045    @InterfaceStability.Stable
046    public class JobID extends org.apache.hadoop.mapreduce.JobID {
047      /**
048       * Constructs a JobID object 
049       * @param jtIdentifier jobTracker identifier
050       * @param id job number
051       */
052      public JobID(String jtIdentifier, int id) {
053        super(jtIdentifier, id);
054      }
055      
056      public JobID() { }
057    
058      /**
059       * Downgrade a new JobID to an old one
060       * @param old a new or old JobID
061       * @return either old or a new JobID build to match old
062       */
063      public static JobID downgrade(org.apache.hadoop.mapreduce.JobID old) {
064        if (old instanceof JobID) {
065          return (JobID) old;
066        } else {
067          return new JobID(old.getJtIdentifier(), old.getId());
068        }
069      }
070    
071      @Deprecated
072      public static JobID read(DataInput in) throws IOException {
073        JobID jobId = new JobID();
074        jobId.readFields(in);
075        return jobId;
076      }
077    
078      /** Construct a JobId object from given string 
079       * @return constructed JobId object or null if the given String is null
080       * @throws IllegalArgumentException if the given string is malformed
081       */
082      public static JobID forName(String str) throws IllegalArgumentException {
083        return (JobID) org.apache.hadoop.mapreduce.JobID.forName(str);
084      }
085      
086      /** 
087       * Returns a regex pattern which matches task IDs. Arguments can 
088       * be given null, in which case that part of the regex will be generic.  
089       * For example to obtain a regex matching <i>any job</i> 
090       * run on the jobtracker started at <i>200707121733</i>, we would use :
091       * <pre> 
092       * JobID.getTaskIDsPattern("200707121733", null);
093       * </pre>
094       * which will return :
095       * <pre> "job_200707121733_[0-9]*" </pre> 
096       * @param jtIdentifier jobTracker identifier, or null
097       * @param jobId job number, or null
098       * @return a regex pattern matching JobIDs
099       */
100      @Deprecated
101      public static String getJobIDsPattern(String jtIdentifier, Integer jobId) {
102        StringBuilder builder = new StringBuilder(JOB).append(SEPARATOR);
103        builder.append(getJobIDsPatternWOPrefix(jtIdentifier, jobId));
104        return builder.toString();
105      }
106      
107      @Deprecated
108      static StringBuilder getJobIDsPatternWOPrefix(String jtIdentifier,
109                                                    Integer jobId) {
110        StringBuilder builder = new StringBuilder();
111        if (jtIdentifier != null) {
112          builder.append(jtIdentifier);
113        } else {
114          builder.append("[^").append(SEPARATOR).append("]*");
115        }
116        builder.append(SEPARATOR)
117          .append(jobId != null ? idFormat.format(jobId) : "[0-9]*");
118        return builder;
119      }
120    
121    }