org.apache.hadoop.mapreduce
Class InputSplit

java.lang.Object
  extended by org.apache.hadoop.mapreduce.InputSplit
Direct Known Subclasses:
CombineFileSplit, DBInputFormat.DBInputSplit, FileSplit, FileSplit

public abstract class InputSplit
extends Object

InputSplit represents the data to be processed by an individual Mapper.

Typically, it presents a byte-oriented view on the input and is the responsibility of RecordReader of the job to process this and present a record-oriented view.

See Also:
InputFormat, RecordReader

Constructor Summary
InputSplit()
           
 
Method Summary
abstract  long getLength()
          Get the size of the split, so that the input splits can be sorted by size.
abstract  String[] getLocations()
          Get the list of nodes by name where the data for the split would be local.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

InputSplit

public InputSplit()
Method Detail

getLength

public abstract long getLength()
                        throws IOException,
                               InterruptedException
Get the size of the split, so that the input splits can be sorted by size.

Returns:
the number of bytes in the split
Throws:
IOException
InterruptedException

getLocations

public abstract String[] getLocations()
                               throws IOException,
                                      InterruptedException
Get the list of nodes by name where the data for the split would be local. The locations do not need to be serialized.

Returns:
a new array of the node nodes.
Throws:
IOException
InterruptedException


Copyright © 2009 The Apache Software Foundation