hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/ErasureCodingWork.java

/**
 * 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.blockmanagement;

import org.apache.hadoop.net.Node;

import java.util.List;
import java.util.Set;

class ErasureCodingWork extends BlockRecoveryWork {
  private final short[] liveBlockIndicies;

  public ErasureCodingWork(BlockInfo block,
      BlockCollection bc,
      DatanodeDescriptor[] srcNodes,
      List<DatanodeDescriptor> containingNodes,
      List<DatanodeStorageInfo> liveReplicaStorages,
      int additionalReplRequired,
      int priority, short[] liveBlockIndicies) {
    super(block, bc, srcNodes, containingNodes,
        liveReplicaStorages, additionalReplRequired, priority);
    this.liveBlockIndicies = liveBlockIndicies;
    BlockManager.LOG.debug("Creating an ErasureCodingWork to recover " + block);
  }

  short[] getLiveBlockIndicies() {
    return liveBlockIndicies;
  }

  @Override
  void chooseTargets(BlockPlacementPolicy blockplacement,
      BlockStoragePolicySuite storagePolicySuite,
      Set<Node> excludedNodes) {
    try {
      // TODO: new placement policy for EC considering multiple writers
      DatanodeStorageInfo[] chosenTargets = blockplacement.chooseTarget(
          getBc().getName(), getAdditionalReplRequired(), getSrcNodes()[0],
          getLiveReplicaStorages(), false, excludedNodes,
          getBlock().getNumBytes(),
          storagePolicySuite.getPolicy(getBc().getStoragePolicyID()));
      setTargets(chosenTargets);
    } finally {
    }
  }
}