hadoop CorruptFileBlockIterator 源码

haddop CorruptFileBlockIterator 代码

文件路径：/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/CorruptFileBlockIterator.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.client.impl;

import java.io.IOException;
import java.util.NoSuchElementException;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.protocol.CorruptFileBlocks;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RemoteIterator;

/**
 * Provides an iterator interface for listCorruptFileBlocks.
 * This class is used by DistributedFileSystem and Hdfs.
 */
@InterfaceAudience.Private
public class CorruptFileBlockIterator implements RemoteIterator<Path> {
  private final DFSClient dfs;
  private final String path;

  private String[] files = null;
  private int fileIdx = 0;
  private String cookie = null;
  private Path nextPath = null;

  private int callsMade = 0;

  public CorruptFileBlockIterator(DFSClient dfs, Path path) throws IOException {
    this.dfs = dfs;
    this.path = path2String(path);
    loadNext();
  }

  /**
   * @return the number of calls made to the DFSClient.
   * This is for debugging and testing purposes.
   */
  public int getCallsMade() {
    return callsMade;
  }

  private String path2String(Path path) {
    return path.toUri().getPath();
  }

  private Path string2Path(String string) {
    return new Path(string);
  }

  private void loadNext() throws IOException {
    if (files == null || fileIdx >= files.length) {
      CorruptFileBlocks cfb = dfs.listCorruptFileBlocks(path, cookie);
      files = cfb.getFiles();
      cookie = cfb.getCookie();
      fileIdx = 0;
      callsMade++;
    }

    if (fileIdx >= files.length) {
      // received an empty response
      // there are no more corrupt file blocks
      nextPath = null;
    } else {
      nextPath = string2Path(files[fileIdx]);
      fileIdx++;
    }
  }


  @Override
  public boolean hasNext() {
    return nextPath != null;
  }


  @Override
  public Path next() throws IOException {
    if (!hasNext()) {
      throw new NoSuchElementException("No more corrupt file blocks");
    }

    Path result = nextPath;
    loadNext();

    return result;
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop BlockReaderFactory 源码

hadoop BlockReaderLocal 源码

hadoop BlockReaderLocalLegacy 源码

hadoop BlockReaderRemote 源码

hadoop BlockReaderUtil 源码

hadoop DfsClientConf 源码

hadoop ExternalBlockReader 源码

hadoop LeaseRenewer 源码

hadoop SnapshotDiffReportGenerator 源码

hadoop package-info 源码