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.io.IOException;
022 import java.text.NumberFormat;
023
024 import org.apache.hadoop.classification.InterfaceAudience.Private;
025 import org.apache.hadoop.classification.InterfaceAudience.Public;
026 import org.apache.hadoop.classification.InterfaceStability.Unstable;
027 import org.apache.hadoop.yarn.util.Records;
028
029 /**
030 * <p>
031 * {@link ReservationId} represents the <em>globally unique</em> identifier for
032 * a reservation.
033 * </p>
034 *
035 * <p>
036 * The globally unique nature of the identifier is achieved by using the
037 * <em>cluster timestamp</em> i.e. start-time of the {@code ResourceManager}
038 * along with a monotonically increasing counter for the reservation.
039 * </p>
040 */
041 @Public
042 @Unstable
043 public abstract class ReservationId implements Comparable<ReservationId> {
044
045 @Private
046 @Unstable
047 public static final String reserveIdStrPrefix = "reservation_";
048 protected long clusterTimestamp;
049 protected long id;
050
051 @Private
052 @Unstable
053 public static ReservationId newInstance(long clusterTimestamp, long id) {
054 ReservationId reservationId = Records.newRecord(ReservationId.class);
055 reservationId.setClusterTimestamp(clusterTimestamp);
056 reservationId.setId(id);
057 reservationId.build();
058 return reservationId;
059 }
060
061 /**
062 * Get the long identifier of the {@link ReservationId} which is unique for
063 * all Reservations started by a particular instance of the
064 * {@code ResourceManager}.
065 *
066 * @return long identifier of the {@link ReservationId}
067 */
068 @Public
069 @Unstable
070 public abstract long getId();
071
072 @Private
073 @Unstable
074 protected abstract void setId(long id);
075
076 /**
077 * Get the <em>start time</em> of the {@code ResourceManager} which is used to
078 * generate globally unique {@link ReservationId}.
079 *
080 * @return <em>start time</em> of the {@code ResourceManager}
081 */
082 @Public
083 @Unstable
084 public abstract long getClusterTimestamp();
085
086 @Private
087 @Unstable
088 protected abstract void setClusterTimestamp(long clusterTimestamp);
089
090 protected abstract void build();
091
092 static final ThreadLocal<NumberFormat> reservIdFormat =
093 new ThreadLocal<NumberFormat>() {
094 @Override
095 public NumberFormat initialValue() {
096 NumberFormat fmt = NumberFormat.getInstance();
097 fmt.setGroupingUsed(false);
098 fmt.setMinimumIntegerDigits(4);
099 return fmt;
100 }
101 };
102
103 @Override
104 public int compareTo(ReservationId other) {
105 if (this.getClusterTimestamp() - other.getClusterTimestamp() == 0) {
106 return getId() > getId() ? 1 : getId() < getId() ? -1 : 0;
107 } else {
108 return this.getClusterTimestamp() > other.getClusterTimestamp() ? 1
109 : this.getClusterTimestamp() < other.getClusterTimestamp() ? -1 : 0;
110 }
111 }
112
113 @Override
114 public String toString() {
115 return reserveIdStrPrefix + this.getClusterTimestamp() + "_"
116 + reservIdFormat.get().format(getId());
117 }
118
119 /**
120 * Parse the string argument as a {@link ReservationId}
121 *
122 * @param reservationId the string representation of the {@link ReservationId}
123 * @return the {@link ReservationId} corresponding to the input string if
124 * valid, null if input is null
125 * @throws IOException if unable to parse the input string
126 */
127 @Public
128 @Unstable
129 public static ReservationId parseReservationId(String reservationId)
130 throws IOException {
131 if (reservationId == null) {
132 return null;
133 }
134 if (!reservationId.startsWith(reserveIdStrPrefix)) {
135 throw new IOException("The specified reservation id is invalid: "
136 + reservationId);
137 }
138 String[] resFields = reservationId.split("_");
139 if (resFields.length != 3) {
140 throw new IOException("The specified reservation id is not parseable: "
141 + reservationId);
142 }
143 return newInstance(Long.parseLong(resFields[1]),
144 Long.parseLong(resFields[2]));
145 }
146
147 @Override
148 public int hashCode() {
149 // generated by eclipse
150 final int prime = 31;
151 int result = 1;
152 result =
153 prime * result
154 + (int) (getClusterTimestamp() ^ (getClusterTimestamp() >>> 32));
155 result = prime * result + (int) (getId() ^ (getId() >>> 32));
156 return result;
157 }
158
159 @Override
160 public boolean equals(Object obj) {
161 // generated by eclipse
162 if (this == obj)
163 return true;
164 if (obj == null)
165 return false;
166 if (getClass() != obj.getClass())
167 return false;
168 ReservationId other = (ReservationId) obj;
169 if (getClusterTimestamp() != other.getClusterTimestamp())
170 return false;
171 if (getId() != other.getId())
172 return false;
173 return true;
174 }
175
176 }