org.jrdf.graph.mem.iterator
Class EmptyClosableIterator

java.lang.Object
  org.jrdf.graph.mem.iterator.EmptyClosableIterator

All Implemented Interfaces:

Iterator<Triple>, ClosableMemIterator<Triple>, ClosableIterator<Triple>

public final class EmptyClosableIterator
extends Object
implements ClosableMemIterator<Triple>

An iterator that returns no triples.

Version:

$Revision: 1045 $

Author:

Andrew Newman

Constructor Summary

EmptyClosableIterator()

Method Summary

boolean	close() Closes the iterator by freeing any resources that it current holds.
boolean	containsHandler(GraphHandler012 handler012, GraphHandler201 handler201, GraphHandler120 handler120) Return true if this iterator contains any of the handlers.
boolean	hasNext() Returns false.
Triple	next() Never returns anything.
void	remove() Not supported by this implementation.

Methods inherited from class java.lang.Object

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

Constructor Detail

EmptyClosableIterator

public EmptyClosableIterator()

Method Detail

hasNext

public boolean hasNext()

Returns false.

Specified by:

hasNext in interface Iterator<Triple>

Returns:

false.

next

public Triple next()
            throws NoSuchElementException

Never returns anything. A call to this will throw NoSuchElementException.

Specified by:

next in interface Iterator<Triple>

Returns:

will not return.

Throws:

NoSuchElementException - always.

remove

public void remove()

Not supported by this implementation. A call to this will throw UnsupportedOperationException.

Specified by:

remove in interface Iterator<Triple>

Throws:

UnsupportedOperationException - always.

close

public boolean close()

Description copied from interface: ClosableIterator

Closes the iterator by freeing any resources that it current holds.

This must be done as soon as possible. Once an iterator is closed none of the operations on a iterator will operate i.e. they will throw an exception.

Specified by:

close in interface ClosableIterator<Triple>

Returns:

true if it was successfully closed.

containsHandler

public boolean containsHandler(GraphHandler012 handler012,
                               GraphHandler201 handler201,
                               GraphHandler120 handler120)

Description copied from interface: ClosableMemIterator

Return true if this iterator contains any of the handlers.

Specified by:

containsHandler in interface ClosableMemIterator<Triple>

Parameters:

handler012 - the 012 handler

handler201 - the 201 handler

handler120 - the 120 handler

Returns:

true if this iterator contains any of the given handlers.