hadoop RawKeyValueIterator 源码

  • 2022-10-20
  • 浏览 (139)

haddop RawKeyValueIterator 代码

文件路径:/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/RawKeyValueIterator.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.mapred;

import java.io.IOException;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.io.DataInputBuffer;
import org.apache.hadoop.util.Progress;

/**
 * <code>RawKeyValueIterator</code> is an iterator used to iterate over
 * the raw keys and values during sort/merge of intermediate data. 
 */
@InterfaceAudience.Private
@InterfaceStability.Unstable
public interface RawKeyValueIterator {
  /** 
   * Gets the current raw key.
   * 
   * @return Gets the current raw key as a DataInputBuffer
   * @throws IOException
   */
  DataInputBuffer getKey() throws IOException;
  
  /** 
   * Gets the current raw value.
   * 
   * @return Gets the current raw value as a DataInputBuffer 
   * @throws IOException
   */
  DataInputBuffer getValue() throws IOException;
  
  /** 
   * Sets up the current key and value (for getKey and getValue).
   * 
   * @return <code>true</code> if there exists a key/value, 
   *         <code>false</code> otherwise. 
   * @throws IOException
   */
  boolean next() throws IOException;
  
  /** 
   * Closes the iterator so that the underlying streams can be closed.
   * 
   * @throws IOException
   */
  void close() throws IOException;
  
  /** Gets the Progress object; this has a float (0.0 - 1.0) 
   * indicating the bytes processed by the iterator so far
   */
  Progress getProgress();
}

相关信息

hadoop 源码目录

相关文章

hadoop AMFeedback 源码

hadoop BackupStore 源码

hadoop BasicTypeSorterBase 源码

hadoop BufferSorter 源码

hadoop CleanupQueue 源码

hadoop Clock 源码

hadoop ClusterStatus 源码

hadoop Counters 源码

hadoop CumulativePeriodicStats 源码

hadoop DeprecatedQueueConfigurationParser 源码

0  赞