Package org.apache.hadoop.io

Class SequenceFile.Sorter.SegmentDescriptor

java.lang.Object

org.apache.hadoop.io.SequenceFile.Sorter.SegmentDescriptor

All Implemented Interfaces:

Comparable

Enclosing class:

SequenceFile.Sorter

public class SequenceFile.Sorter.SegmentDescriptor
extends Object
implements Comparable

This class defines a merge segment. This class can be subclassed to provide a customized cleanup method implementation. In this implementation, cleanup closes the file handle and deletes the file

Constructor Summary

Constructors

Constructor	Description
SegmentDescriptor(long segmentOffset, long segmentLength, Path segmentPathName)	Constructs a segment

Method Summary

Modifier and Type	Method	Description
void	cleanup()	The default cleanup.
int	compareTo(Object o)
void	doSync()	Do the sync checks.
boolean	equals(Object o)
DataOutputBuffer	getKey()
int	hashCode()
boolean	nextRawKey()	Fills up the rawKey object with the key returned by the Reader.
int	nextRawValue(SequenceFile.ValueBytes rawValue)	Fills up the passed rawValue with the value corresponding to the key read earlier.
void	preserveInput(boolean preserve)	Whether to delete the files when no longer needed.
boolean	shouldPreserveInput()

Methods inherited from class java.lang.Object

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

Constructor Details

SegmentDescriptor

public SegmentDescriptor(long segmentOffset,
 long segmentLength,
 Path segmentPathName)

Constructs a segment

Parameters:

segmentOffset - the offset of the segment in the file

segmentLength - the length of the segment

segmentPathName - the path name of the file containing the segment

Method Details

doSync

public void doSync()

Do the sync checks.

preserveInput

public void preserveInput(boolean preserve)

Whether to delete the files when no longer needed.

Parameters:

preserve - input boolean preserve.

shouldPreserveInput

public boolean shouldPreserveInput()

compareTo

public int compareTo(Object o)

Specified by:

compareTo in interface Comparable

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

nextRawKey

public boolean nextRawKey()
                   throws IOException

Fills up the rawKey object with the key returned by the Reader.

Returns:

true if there is a key returned; false, otherwise

Throws:

IOException - raised on errors performing I/O.

nextRawValue

public int nextRawValue(SequenceFile.ValueBytes rawValue)
                 throws IOException

Fills up the passed rawValue with the value corresponding to the key read earlier.

Parameters:

rawValue - input ValueBytes rawValue.

Returns:

the length of the value

Throws:

IOException - raised on errors performing I/O.

getKey

public DataOutputBuffer getKey()

Returns:

Returns the stored rawKey

cleanup

public void cleanup()
             throws IOException

The default cleanup. Subclasses can override this with a custom cleanup.

Throws:

IOException - raised on errors performing I/O.