| /** |
| * 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.*; |
| import java.util.List; |
| |
| import org.apache.hadoop.hdfs.protocol.Block; |
| import org.apache.hadoop.hdfs.protocol.DatanodeInfo; |
| import org.apache.hadoop.hdfs.server.namenode.DatanodeDescriptor.BlockTargetPair; |
| import org.apache.hadoop.io.*; |
| |
| |
| /**************************************************** |
| * A BlockCommand is an instruction to a datanode |
| * regarding some blocks under its control. It tells |
| * the DataNode to either invalidate a set of indicated |
| * blocks, or to copy a set of indicated blocks to |
| * another DataNode. |
| * |
| ****************************************************/ |
| public class BlockCommand extends DatanodeCommand { |
| Block blocks[]; |
| DatanodeInfo targets[][]; |
| |
| public BlockCommand() {} |
| |
| /** |
| * Create BlockCommand for transferring blocks to another datanode |
| * @param blocktargetlist blocks to be transferred |
| */ |
| public BlockCommand(int action, List<BlockTargetPair> blocktargetlist) { |
| super(action); |
| |
| blocks = new Block[blocktargetlist.size()]; |
| targets = new DatanodeInfo[blocks.length][]; |
| for(int i = 0; i < blocks.length; i++) { |
| BlockTargetPair p = blocktargetlist.get(i); |
| blocks[i] = p.block; |
| targets[i] = p.targets; |
| } |
| } |
| |
| private static final DatanodeInfo[][] EMPTY_TARGET = {}; |
| |
| /** |
| * Create BlockCommand for the given action |
| * @param blocks blocks related to the action |
| */ |
| public BlockCommand(int action, Block blocks[]) { |
| super(action); |
| this.blocks = blocks; |
| this.targets = EMPTY_TARGET; |
| } |
| |
| public Block[] getBlocks() { |
| return blocks; |
| } |
| |
| public DatanodeInfo[][] getTargets() { |
| return targets; |
| } |
| |
| /////////////////////////////////////////// |
| // Writable |
| /////////////////////////////////////////// |
| static { // register a ctor |
| WritableFactories.setFactory |
| (BlockCommand.class, |
| new WritableFactory() { |
| public Writable newInstance() { return new BlockCommand(); } |
| }); |
| } |
| |
| public void write(DataOutput out) throws IOException { |
| super.write(out); |
| out.writeInt(blocks.length); |
| for (int i = 0; i < blocks.length; i++) { |
| blocks[i].write(out); |
| } |
| out.writeInt(targets.length); |
| for (int i = 0; i < targets.length; i++) { |
| out.writeInt(targets[i].length); |
| for (int j = 0; j < targets[i].length; j++) { |
| targets[i][j].write(out); |
| } |
| } |
| } |
| |
| public void readFields(DataInput in) throws IOException { |
| super.readFields(in); |
| this.blocks = new Block[in.readInt()]; |
| for (int i = 0; i < blocks.length; i++) { |
| blocks[i] = new Block(); |
| blocks[i].readFields(in); |
| } |
| |
| this.targets = new DatanodeInfo[in.readInt()][]; |
| for (int i = 0; i < targets.length; i++) { |
| this.targets[i] = new DatanodeInfo[in.readInt()]; |
| for (int j = 0; j < targets[i].length; j++) { |
| targets[i][j] = new DatanodeInfo(); |
| targets[i][j].readFields(in); |
| } |
| } |
| } |
| } |