| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.hdfs.server.protocol; |
| |
| import java.io.DataInput; |
| import java.io.DataOutput; |
| import java.io.IOException; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.io.Writable; |
| import org.apache.hadoop.io.WritableFactory; |
| import org.apache.hadoop.io.WritableFactories; |
| import org.apache.hadoop.io.WritableUtils; |
| import org.apache.avro.reflect.Union; |
| |
| /** |
| * Base class for data-node command. |
| * Issued by the name-node to notify data-nodes what should be done. |
| */ |
| |
| // Declare subclasses for Avro's denormalized representation |
| @Union({Void.class, |
| DatanodeCommand.Register.class, DatanodeCommand.Finalize.class, |
| BlockCommand.class, UpgradeCommand.class, |
| BlockRecoveryCommand.class, KeyUpdateCommand.class}) |
| |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public abstract class DatanodeCommand extends ServerCommand { |
| static class Register extends DatanodeCommand { |
| private Register() {super(DatanodeProtocol.DNA_REGISTER);} |
| public void readFields(DataInput in) {} |
| public void write(DataOutput out) {} |
| } |
| |
| public static class Finalize extends DatanodeCommand { |
| String blockPoolId; |
| private Finalize() { |
| super(DatanodeProtocol.DNA_FINALIZE); |
| } |
| |
| public Finalize(String bpid) { |
| super(DatanodeProtocol.DNA_FINALIZE); |
| blockPoolId = bpid; |
| } |
| |
| public String getBlockPoolId() { |
| return blockPoolId; |
| } |
| |
| public void readFields(DataInput in) throws IOException { |
| blockPoolId = WritableUtils.readString(in); |
| } |
| public void write(DataOutput out) throws IOException { |
| WritableUtils.writeString(out, blockPoolId); |
| } |
| } |
| |
| static { // register a ctor |
| WritableFactories.setFactory(Register.class, |
| new WritableFactory() { |
| public Writable newInstance() {return new Register();} |
| }); |
| WritableFactories.setFactory(Finalize.class, |
| new WritableFactory() { |
| public Writable newInstance() {return new Finalize();} |
| }); |
| } |
| |
| public static final DatanodeCommand REGISTER = new Register(); |
| |
| public DatanodeCommand() { |
| super(); |
| } |
| |
| DatanodeCommand(int action) { |
| super(action); |
| } |
| } |