org.apache.hadoop.mapred.join
Class CompositeInputSplit

java.lang.Object
  org.apache.hadoop.mapred.join.CompositeInputSplit

All Implemented Interfaces:

Writable, InputSplit

public class CompositeInputSplit
extends Object
implements InputSplit

This InputSplit contains a set of child InputSplits. Any InputSplit inserted into this collection must have a public default constructor.

Constructor Summary

CompositeInputSplit()

CompositeInputSplit(int capacity)

Method Summary

void	add(InputSplit s) Add an InputSplit to this collection.
InputSplit	get(int i) Get ith child InputSplit.
long	getLength() Return the aggregate length of all child InputSplits currently added.
long	getLength(int i) Get the length of ith child InputSplit.
String[]	getLocation(int i) getLocations from ith InputSplit.
String[]	getLocations() Collect a set of hosts from all child InputSplits.
void	readFields(DataInput in) Deserialize the fields of this object from in.
void	write(DataOutput out) Write splits in the following format.

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeInputSplit

public CompositeInputSplit()

CompositeInputSplit

public CompositeInputSplit(int capacity)

Method Detail

add

public void add(InputSplit s)
         throws IOException

Add an InputSplit to this collection.

Throws:

IOException - If capacity was not specified during construction or if capacity has been reached.

get

public InputSplit get(int i)

Get ith child InputSplit.

getLength

public long getLength()
               throws IOException

Return the aggregate length of all child InputSplits currently added.

Specified by:

getLength in interface InputSplit

Returns:

the number of bytes in the input split.

Throws:

IOException

getLength

public long getLength(int i)
               throws IOException

Get the length of ith child InputSplit.

Throws:

IOException

getLocations

public String[] getLocations()
                      throws IOException

Collect a set of hosts from all child InputSplits.

Specified by:

getLocations in interface InputSplit

Returns:

list of hostnames where data of the InputSplit is located as an array of Strings.

Throws:

IOException

getLocation

public String[] getLocation(int i)
                     throws IOException

getLocations from ith InputSplit.

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Write splits in the following format. <count><class1><class2>...<classn><split1><split2>...<splitn>

Specified by:

write in interface Writable

Parameters:

out - DataOuput to serialize this object into.

Throws:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

Specified by:

readFields in interface Writable

Parameters:

in - DataInput to deseriablize this object from.

Throws:

IOException - If the child InputSplit cannot be read, typically for faliing access checks.