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
019package org.apache.hadoop.yarn.api.records;
020
021import java.text.NumberFormat;
022
023import org.apache.hadoop.classification.InterfaceAudience.Private;
024import org.apache.hadoop.classification.InterfaceAudience.Public;
025import org.apache.hadoop.classification.InterfaceStability.Stable;
026import org.apache.hadoop.classification.InterfaceStability.Unstable;
027
028/**
029 * <p><code>ApplicationAttemptId</code> denotes the particular <em>attempt</em>
030 * of an <code>ApplicationMaster</code> for a given {@link ApplicationId}.</p>
031 * 
032 * <p>Multiple attempts might be needed to run an application to completion due
033 * to temporal failures of the <code>ApplicationMaster</code> such as hardware
034 * failures, connectivity issues etc. on the node on which it was scheduled.</p>
035 */
036@Public
037@Stable
038public abstract class ApplicationAttemptId implements
039    Comparable<ApplicationAttemptId> {
040  
041  /**
042   * Get the <code>ApplicationId</code> of the <code>ApplicationAttempId</code>. 
043   * @return <code>ApplicationId</code> of the <code>ApplicationAttempId</code>
044   */
045  @Public
046  @Stable
047  public abstract ApplicationId getApplicationId();
048  
049  @Private
050  @Unstable
051  public abstract void setApplicationId(ApplicationId appID);
052  
053  /**
054   * Get the <code>attempt id</code> of the <code>Application</code>.
055   * @return <code>attempt id</code> of the <code>Application</code>
056   */
057  public abstract int getAttemptId();
058  
059  @Private
060  @Unstable
061  public abstract void setAttemptId(int attemptId);
062
063  static final ThreadLocal<NumberFormat> attemptIdFormat =
064      new ThreadLocal<NumberFormat>() {
065        @Override
066        public NumberFormat initialValue() {
067          NumberFormat fmt = NumberFormat.getInstance();
068          fmt.setGroupingUsed(false);
069          fmt.setMinimumIntegerDigits(6);
070          return fmt;
071        }
072      };
073
074  @Override
075  public int hashCode() {
076    // Generated by eclipse.
077    final int prime = 31;
078    int result = 1;
079    ApplicationId appId = getApplicationId();
080    result = prime * result +  appId.hashCode();
081    result = prime * result + getAttemptId();
082    return result;
083  }
084
085  @Override
086  public boolean equals(Object obj) {
087    if (this == obj)
088      return true;
089    if (obj == null)
090      return false;
091    if (getClass() != obj.getClass())
092      return false;
093    ApplicationAttemptId other = (ApplicationAttemptId) obj;
094    if (!this.getApplicationId().equals(other.getApplicationId()))
095      return false;
096    if (this.getAttemptId() != other.getAttemptId())
097      return false;
098    return true;
099  }
100
101  @Override
102  public int compareTo(ApplicationAttemptId other) {
103    int compareAppIds = this.getApplicationId().compareTo(
104        other.getApplicationId());
105    if (compareAppIds == 0) {
106      return this.getAttemptId() - other.getAttemptId();
107    } else {
108      return compareAppIds;
109    }
110  }
111
112  @Override
113  public String toString() {
114    StringBuilder sb = new StringBuilder("appattempt_");
115    sb.append(this.getApplicationId().getClusterTimestamp()).append("_");
116    sb.append(ApplicationId.appIdFormat.get().format(
117        this.getApplicationId().getId()));
118    sb.append("_").append(attemptIdFormat.get().format(getAttemptId()));
119    return sb.toString();
120  }
121}