com.bigdata.rdf.spo
Class DistinctSPOIterator

java.lang.Object
  com.bigdata.rdf.spo.DistinctSPOIterator

All Implemented Interfaces:

ICloseableIterator<ISPO>, Iterator<ISPO>

public class DistinctSPOIterator
extends Object
implements ICloseableIterator<ISPO>

Iterator using a BTree filter out duplicate (s,p,o) tuples.

Version:

$Id: DistinctSPOIterator.java 2265 2009-10-26 12:51:06Z thompsonbry $

Author:

Bryan Thompson

See Also:

SPORelation.distinctSPOIterator(ICloseableIterator)

Constructor Summary

DistinctSPOIterator(SPORelation spoRelation, ICloseableIterator<ISPO> src)

Method Summary

void	close() Closes the iterator, releasing any associated resources.
boolean	hasNext() Returns immediately if there is an element waiting.
ISPO	next()
void	remove()

Methods inherited from class java.lang.Object

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

Constructor Detail

DistinctSPOIterator

public DistinctSPOIterator(SPORelation spoRelation,
                           ICloseableIterator<ISPO> src)

Parameters:

src - The source iterator.

Method Detail

close

public void close()

Description copied from interface: ICloseableIterator

Closes the iterator, releasing any associated resources. This method MAY be invoked safely if the iterator is already closed.

Note: Implementations that support Iterator.remove() MUST NOT eagerly close the iterator when it is exhausted since that would make it impossible to remove the last visited statement. Instead they MUST wait for an explicit ICloseableIterator.close() by the application.

Specified by:

close in interface ICloseableIterator<ISPO>

hasNext

public boolean hasNext()

Returns immediately if there is an element waiting. Otherwise, scans ahead until it finds an element which has not already been visited. It then add the element to the set of elements already seen and saves a reference to that element to be returned by next().

Specified by:

hasNext in interface Iterator<ISPO>

next

public ISPO next()

Specified by:

next in interface Iterator<ISPO>

remove

public void remove()

Specified by:

remove in interface Iterator<ISPO>