import org.apache.hadoop.hdfs.server.namenode.ha.proto.HAZKInfoProtos.ActiveNodeInfo; //导入依赖的package包/类
@Override
protected HAServiceTarget dataToTarget(byte[] data) {
  ActiveNodeInfo proto;
  try {
    proto = ActiveNodeInfo.parseFrom(data);
  } catch (InvalidProtocolBufferException e) {
    throw new RuntimeException("Invalid data in ZK: " +
        StringUtils.byteToHexString(data));
  }
  NNHAServiceTarget ret = new NNHAServiceTarget(
      conf, proto.getNameserviceId(), proto.getNamenodeId());
  InetSocketAddress addressFromProtobuf = new InetSocketAddress(
      proto.getHostname(), proto.getPort());
  
  if (!addressFromProtobuf.equals(ret.getAddress())) {
    throw new RuntimeException("Mismatched address stored in ZK for " +
        ret + ": Stored protobuf was " + proto + ", address from our own " +
        "configuration for this NameNode was " + ret.getAddress());
  }
  
  ret.setZkfcPort(proto.getZkfcPort());
  return ret;
}
 

import org.apache.hadoop.hdfs.server.namenode.ha.proto.HAZKInfoProtos.ActiveNodeInfo; //导入依赖的package包/类
@Override
protected HAServiceTarget dataToTarget(byte[] data) {
  ActiveNodeInfo proto;
  try {
    proto = ActiveNodeInfo.parseFrom(data);
  } catch (InvalidProtocolBufferException e) {
    throw new RuntimeException("Invalid data in ZK: " +
        StringUtils.byteToHexString(data));
  }
  JobTrackerHAServiceTarget ret = new JobTrackerHAServiceTarget(
      conf, proto.getNamenodeId());
  InetSocketAddress addressFromProtobuf = new InetSocketAddress(
      proto.getHostname(), proto.getPort());
  
  if (!addressFromProtobuf.equals(ret.getAddress())) {
    throw new RuntimeException("Mismatched address stored in ZK for " +
        ret + ": Stored protobuf was " + addressFromProtobuf + ", address from our own " +
        "configuration for this JobTracker was " + ret.getAddress());
  }
  
  ret.setZkfcPort(proto.getZkfcPort());
  return ret;
}
 

import org.apache.hadoop.hdfs.server.namenode.ha.proto.HAZKInfoProtos.ActiveNodeInfo; //导入依赖的package包/类
@Override
protected byte[] targetToData(HAServiceTarget target) {
  InetSocketAddress addr = target.getAddress();

  return ActiveNodeInfo.newBuilder()
    .setHostname(addr.getHostName())
    .setPort(addr.getPort())
    .setZkfcPort(target.getZKFCAddress().getPort())
    .setNameserviceId(localNNTarget.getNameServiceId())
    .setNamenodeId(localNNTarget.getNameNodeId())
    .build()
    .toByteArray();
}
 

import org.apache.hadoop.hdfs.server.namenode.ha.proto.HAZKInfoProtos.ActiveNodeInfo; //导入依赖的package包/类
@Override
protected byte[] targetToData(HAServiceTarget target) {
  InetSocketAddress addr = target.getAddress();

  return ActiveNodeInfo.newBuilder()
    .setHostname(addr.getHostName())
    .setPort(addr.getPort())
    .setZkfcPort(target.getZKFCAddress().getPort())
    .setNameserviceId(localJTTarget.getLogicalName())
    .setNamenodeId(localJTTarget.getJobTrackerId())
    .build()
    .toByteArray();
}