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.hbase;
020
021import java.io.IOException;
022import java.util.UUID;
023
024import org.apache.yetus.audience.InterfaceAudience;
025import org.apache.hadoop.hbase.exceptions.DeserializationException;
026import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
027import org.apache.hadoop.hbase.shaded.protobuf.generated.ClusterIdProtos;
028import org.apache.hadoop.hbase.util.Bytes;
029
030/**
031 * The identifier for this cluster.
032 * It is serialized to the filesystem and up into zookeeper.  This is a container for the id.
033 * Also knows how to serialize and deserialize the cluster id.
034 */
035@InterfaceAudience.Private
036public class ClusterId {
037  private final String id;
038
039  /**
040   * New ClusterID.  Generates a uniqueid.
041   */
042  public ClusterId() {
043    this(UUID.randomUUID().toString());
044  }
045
046  public ClusterId(final String uuid) {
047    this.id = uuid;
048  }
049
050  /**
051   * @return The clusterid serialized using pb w/ pb magic prefix
052   */
053  public byte [] toByteArray() {
054    return ProtobufUtil.prependPBMagic(convert().toByteArray());
055  }
056
057  /**
058   * @param bytes A pb serialized {@link ClusterId} instance with pb magic prefix
059   * @return An instance of {@link ClusterId} made from <code>bytes</code>
060   * @throws DeserializationException
061   * @see #toByteArray()
062   */
063  public static ClusterId parseFrom(final byte [] bytes) throws DeserializationException {
064    if (ProtobufUtil.isPBMagicPrefix(bytes)) {
065      int pblen = ProtobufUtil.lengthOfPBMagic();
066      ClusterIdProtos.ClusterId.Builder builder = ClusterIdProtos.ClusterId.newBuilder();
067      ClusterIdProtos.ClusterId cid = null;
068      try {
069        ProtobufUtil.mergeFrom(builder, bytes, pblen, bytes.length - pblen);
070        cid = builder.build();
071      } catch (IOException e) {
072        throw new DeserializationException(e);
073      }
074      return convert(cid);
075    } else {
076      // Presume it was written out this way, the old way.
077      return new ClusterId(Bytes.toString(bytes));
078    }
079  }
080
081  /**
082   * @return A pb instance to represent this instance.
083   */
084  public ClusterIdProtos.ClusterId convert() {
085    ClusterIdProtos.ClusterId.Builder builder = ClusterIdProtos.ClusterId.newBuilder();
086    return builder.setClusterId(this.id).build();
087  }
088
089  /**
090   * @param cid
091   * @return A {@link ClusterId} made from the passed in <code>cid</code>
092   */
093  public static ClusterId convert(final ClusterIdProtos.ClusterId cid) {
094    return new ClusterId(cid.getClusterId());
095  }
096
097  /**
098   * @see java.lang.Object#toString()
099   */
100  @Override
101  public String toString() {
102    return this.id;
103  }
104}