| /** |
| * 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.util.List; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.hdfs.protocol.Block; |
| import org.apache.hadoop.hdfs.protocol.DatanodeInfo; |
| import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor.BlockTargetPair; |
| |
| /**************************************************** |
| * 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. |
| * |
| ****************************************************/ |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public class BlockCommand extends DatanodeCommand { |
| |
| /** |
| * This constant is used to indicate that the block deletion does not need |
| * explicit ACK from the datanode. When a block is put into the list of blocks |
| * to be deleted, it's size is set to this constant. We assume that no block |
| * would actually have this size. Otherwise, we would miss ACKs for blocks |
| * with such size. Positive number is used for compatibility reasons. |
| */ |
| public static final long NO_ACK = Long.MAX_VALUE; |
| |
| String poolId; |
| Block blocks[]; |
| DatanodeInfo targets[][]; |
| |
| /** |
| * Create BlockCommand for transferring blocks to another datanode |
| * @param blocktargetlist blocks to be transferred |
| */ |
| public BlockCommand(int action, String poolId, |
| List<BlockTargetPair> blocktargetlist) { |
| super(action); |
| this.poolId = poolId; |
| 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, String poolId, Block blocks[]) { |
| this(action, poolId, blocks, EMPTY_TARGET); |
| } |
| |
| /** |
| * Create BlockCommand for the given action |
| * @param blocks blocks related to the action |
| */ |
| public BlockCommand(int action, String poolId, Block[] blocks, |
| DatanodeInfo[][] targets) { |
| super(action); |
| this.poolId = poolId; |
| this.blocks = blocks; |
| this.targets = targets; |
| } |
| |
| public String getBlockPoolId() { |
| return poolId; |
| } |
| |
| public Block[] getBlocks() { |
| return blocks; |
| } |
| |
| public DatanodeInfo[][] getTargets() { |
| return targets; |
| } |
| } |