org.jrdf.graph.local.iterator
Class GraphIterator

java.lang.Object
  org.jrdf.graph.local.iterator.GraphIterator

All Implemented Interfaces:

Iterator<Triple>, ClosableLocalIterator<Triple>, ClosableIterator<Triple>

public final class GraphIterator
extends Object
implements ClosableLocalIterator<Triple>

An iterator that iterates over an entire graph. Relies on internal iterators which iterate over all entries in the first map, the maps it points to, and the sets they point to. The itemIterator is used to indicate the current position. It will always be set to return the next value until it reaches the end of the graph.

Version:

$Revision: 1881 $

Author:

Paul Gearon, Andrew Newman

Constructor Summary

GraphIterator(GraphHandler newHandler)
Constructor.

Method Summary

boolean	close() Closes the iterator by freeing any resources that it current holds.
boolean	hasNext() Returns true if the iteration has more elements.
Triple	next() Returns the next element in the iteration.
void	remove() Implemented for java.util.Iterator.

Methods inherited from class java.lang.Object

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

Constructor Detail

GraphIterator

public GraphIterator(GraphHandler newHandler)

Constructor. Sets up the internal iterators.

Throws:

IllegalArgumentException - Must be created with implementations from the memory package.

Method Detail

hasNext

public boolean hasNext()

Returns true if the iteration has more elements.

Specified by:

hasNext in interface Iterator<Triple>

Returns:

true If there is an element to be read.

next

public Triple next()
            throws NoSuchElementException

Returns the next element in the iteration.

Specified by:

next in interface Iterator<Triple>

Returns:

the next element in the iteration.

Throws:

NoSuchElementException - iteration has no more elements.

remove

public void remove()

Implemented for java.util.Iterator.

Specified by:

remove in interface Iterator<Triple>

close

public boolean close()

Closes the iterator by freeing any resources that it current holds. Nothing to be done for this class.

Specified by:

close in interface ClosableIterator<Triple>

Returns:

true indicating success.