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.yarn.api.records;
020    
021    import java.text.NumberFormat;
022    
023    import org.apache.hadoop.classification.InterfaceAudience.Private;
024    import org.apache.hadoop.classification.InterfaceAudience.Public;
025    import org.apache.hadoop.classification.InterfaceStability.Stable;
026    import org.apache.hadoop.classification.InterfaceStability.Unstable;
027    import org.apache.hadoop.yarn.util.Records;
028    
029    /**
030     * <p><code>ApplicationAttemptId</code> denotes the particular <em>attempt</em>
031     * of an <code>ApplicationMaster</code> for a given {@link ApplicationId}.</p>
032     * 
033     * <p>Multiple attempts might be needed to run an application to completion due
034     * to temporal failures of the <code>ApplicationMaster</code> such as hardware
035     * failures, connectivity issues etc. on the node on which it was scheduled.</p>
036     */
037    @Public
038    @Stable
039    public abstract class ApplicationAttemptId implements
040        Comparable<ApplicationAttemptId> {
041    
042      @Private
043      @Unstable
044      public static final String appAttemptIdStrPrefix = "appattempt_";
045    
046      @Private
047      @Unstable
048      public static ApplicationAttemptId newInstance(ApplicationId appId,
049          int attemptId) {
050        ApplicationAttemptId appAttemptId =
051            Records.newRecord(ApplicationAttemptId.class);
052        appAttemptId.setApplicationId(appId);
053        appAttemptId.setAttemptId(attemptId);
054        appAttemptId.build();
055        return appAttemptId;
056      }
057    
058      /**
059       * Get the <code>ApplicationId</code> of the <code>ApplicationAttempId</code>. 
060       * @return <code>ApplicationId</code> of the <code>ApplicationAttempId</code>
061       */
062      @Public
063      @Stable
064      public abstract ApplicationId getApplicationId();
065      
066      @Private
067      @Unstable
068      protected abstract void setApplicationId(ApplicationId appID);
069      
070      /**
071       * Get the <code>attempt id</code> of the <code>Application</code>.
072       * @return <code>attempt id</code> of the <code>Application</code>
073       */
074      @Public
075      @Stable
076      public abstract int getAttemptId();
077      
078      @Private
079      @Unstable
080      protected abstract void setAttemptId(int attemptId);
081    
082      static final ThreadLocal<NumberFormat> attemptIdFormat =
083          new ThreadLocal<NumberFormat>() {
084            @Override
085            public NumberFormat initialValue() {
086              NumberFormat fmt = NumberFormat.getInstance();
087              fmt.setGroupingUsed(false);
088              fmt.setMinimumIntegerDigits(6);
089              return fmt;
090            }
091          };
092    
093      @Override
094      public int hashCode() {
095        // Generated by eclipse.
096        final int prime = 347671;
097        int result = 5501;
098        ApplicationId appId = getApplicationId();
099        result = prime * result +  appId.hashCode();
100        result = prime * result + getAttemptId();
101        return result;
102      }
103    
104      @Override
105      public boolean equals(Object obj) {
106        if (this == obj)
107          return true;
108        if (obj == null)
109          return false;
110        if (getClass() != obj.getClass())
111          return false;
112        ApplicationAttemptId other = (ApplicationAttemptId) obj;
113        if (!this.getApplicationId().equals(other.getApplicationId()))
114          return false;
115        if (this.getAttemptId() != other.getAttemptId())
116          return false;
117        return true;
118      }
119    
120      @Override
121      public int compareTo(ApplicationAttemptId other) {
122        int compareAppIds = this.getApplicationId().compareTo(
123            other.getApplicationId());
124        if (compareAppIds == 0) {
125          return this.getAttemptId() - other.getAttemptId();
126        } else {
127          return compareAppIds;
128        }
129      }
130    
131      @Override
132      public String toString() {
133        StringBuilder sb = new StringBuilder(appAttemptIdStrPrefix);
134        sb.append(this.getApplicationId().getClusterTimestamp()).append("_");
135        sb.append(ApplicationId.appIdFormat.get().format(
136            this.getApplicationId().getId()));
137        sb.append("_").append(attemptIdFormat.get().format(getAttemptId()));
138        return sb.toString();
139      }
140    
141      protected abstract void build();
142    }