public class DelegatingInputFormat<K,V> extends Object implements InputFormat<K,V>
InputFormat
that delegates behaviour of paths to multiple other
InputFormats.构造器和说明 |
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DelegatingInputFormat() |
限定符和类型 | 方法和说明 |
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RecordReader<K,V> |
getRecordReader(InputSplit split,
JobConf conf,
Reporter reporter)
Get the
RecordReader for the given InputSplit . |
InputSplit[] |
getSplits(JobConf conf,
int numSplits)
Logically split the set of input files for the job.
|
public InputSplit[] getSplits(JobConf conf, int numSplits) throws IOException
InputFormat
Each InputSplit
is then assigned to an individual Mapper
for processing.
Note: The split is a logical split of the inputs and the input files are not physically split into chunks. For e.g. a split could be <input-file-path, start, offset> tuple.
getSplits
在接口中 InputFormat<K,V>
conf
- job configuration.numSplits
- the desired number of splits, a hint.InputSplit
s for the job.IOException
public RecordReader<K,V> getRecordReader(InputSplit split, JobConf conf, Reporter reporter) throws IOException
InputFormat
RecordReader
for the given InputSplit
.
It is the responsibility of the RecordReader
to respect
record boundaries while processing the logical split to present a
record-oriented view to the individual task.
getRecordReader
在接口中 InputFormat<K,V>
split
- the InputSplit
conf
- the job that this split belongs toRecordReader
IOException
Copyright © 2009 The Apache Software Foundation