org.apache.hadoop.tools.distcp2.mapred

类 UniformSizeInputFormat

java.lang.Object

org.apache.hadoop.mapreduce.InputFormat<Text,FileStatus>

org.apache.hadoop.tools.distcp2.mapred.UniformSizeInputFormat

public class UniformSizeInputFormat
extends InputFormat<Text,FileStatus>

UniformSizeInputFormat extends the InputFormat<> class, to produce input-splits for DistCp. It looks at the copy-listing and groups the contents into input-splits such that the total-number of bytes to be copied for each input split is uniform.

构造器概要

构造器

构造器和说明
UniformSizeInputFormat()

方法概要

方法

限定符和类型	方法和说明
RecordReader<Text,FileStatus>	createRecordReader(InputSplit split, TaskAttemptContext context) Implementation of InputFormat::createRecordReader().
List<InputSplit>	getSplits(JobContext context) Implementation of InputFormat::getSplits().

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

UniformSizeInputFormat

public UniformSizeInputFormat()

方法详细资料

getSplits

public List<InputSplit> getSplits(JobContext context)
                           throws IOException,
                                  InterruptedException

Implementation of InputFormat::getSplits(). Returns a list of InputSplits, such that the number of bytes to be copied for all the splits are approximately equal.

指定者:

getSplits 在类中 InputFormat<Text,FileStatus>

参数:

context - JobContext for the job.

返回:

The list of uniformly-distributed input-splits.

抛出:

IOException: - On failure.

InterruptedException

IOException

createRecordReader

public RecordReader<Text,FileStatus> createRecordReader(InputSplit split,
                                               TaskAttemptContext context)
                                                 throws IOException,
                                                        InterruptedException

Implementation of InputFormat::createRecordReader().

指定者:

createRecordReader 在类中 InputFormat<Text,FileStatus>

参数:

split - The split for which the RecordReader is sought.

context - The context of the current task-attempt.

返回:

A SequenceFileRecordReader instance, (since the copy-listing is a simple sequence-file.)

抛出:

IOException

InterruptedException