content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.master.file;
  
  import com.google.common.base.Throwables;
  
  import java.io.IOException;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.List;
  import java.util.concurrent.ConcurrentLinkedQueue;
  
  /**
   * Class for tracking which blocks need to be deleted, and deleting them on close.
   */
  public final class DefaultBlockDeletionContext implements BlockDeletionContext {
    private final List<BlockDeletionListener> mListeners;
    private final ConcurrentLinkedQueue<Long> mBlocks;
  
    /**
     * @param listeners listeners to call for each deleted block when the context is closed
     */
    public DefaultBlockDeletionContext(BlockDeletionListener... listeners) {
      mListeners = Arrays.asList(listeners);
      mBlocks = new ConcurrentLinkedQueue<>();
    }
  
    @Override
    public void registerBlocksForDeletion(Collection<Long> blockIds) {
      mBlocks.addAll(blockIds);
    }
  
    @Override
    public void registerBlockForDeletion(long blockId) {
      mBlocks.add(blockId);
    }
  
    @Override
    public void close() throws IOException {
      // Prevent accidental modification from the listeners
      Collection<Long> viewOnlyBlocks = Collections.unmodifiableCollection(mBlocks);
      // Make sure every listener gets called, even if some throw exceptions.
      Throwable thrown = null;
      for (BlockDeletionListener listener : mListeners) {
        try {
          listener.process(viewOnlyBlocks);
        } catch (Throwable t) {
          if (thrown != null) {
            thrown.addSuppressed(t);
          } else {
            thrown = t;
          }
        }
      }
      if (thrown != null) {
        Throwables.propagateIfPossible(thrown, IOException.class);
        throw new RuntimeException(thrown);
      }
    }
  }
  