info.aduna.iteration
Class IntersectIteration<E,X extends Exception>

java.lang.Object
  info.aduna.iteration.CloseableIterationBase<E,X>
      info.aduna.iteration.IterationWrapper<E,X>
          info.aduna.iteration.FilterIteration<E,X>
              info.aduna.iteration.IntersectIteration<E,X>

All Implemented Interfaces:

CloseableIteration<E,X>, Iteration<E,X>

Direct Known Subclasses:

IntersectIterator

public class IntersectIteration<E,X extends Exception>
extends FilterIteration<E,X>

An Iteration that returns the intersection of the results of two Iterations. Optionally, the Iteration can be configured to filter duplicates from the returned elements.

Note that duplicates can also be filtered by wrapping this Iteration in a DistinctIteration, but that has a bit more overhead as it adds a second hash table lookup.

Field Summary

Fields inherited from class info.aduna.iteration.IterationWrapper

wrappedIter

Fields inherited from class info.aduna.iteration.CloseableIterationBase

logger

Constructor Summary

IntersectIteration(Iteration<? extends E,? extends X> arg1, Iteration<? extends E,? extends X> arg2)
Creates a new IntersectIteration that returns the intersection of the results of two Iterations.

IntersectIteration(Iteration<? extends E,? extends X> arg1, Iteration<? extends E,? extends X> arg2, boolean distinct)
Creates a new IntersectIteration that returns the intersection of the results of two Iterations.

Method Summary

protected boolean	accept(E object) Returns true if the object is in the set of elements of the second argument.
protected void	handleClose() Closed this Iteration and also closes the wrapped Iteration if it is a CloseableIteration.

Methods inherited from class info.aduna.iteration.FilterIteration

hasNext, next

Methods inherited from class info.aduna.iteration.IterationWrapper

remove

Methods inherited from class info.aduna.iteration.CloseableIterationBase

close, isClosed

Methods inherited from class java.lang.Object

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

Constructor Detail

IntersectIteration

public IntersectIteration(Iteration<? extends E,? extends X> arg1,
                          Iteration<? extends E,? extends X> arg2)

Creates a new IntersectIteration that returns the intersection of the results of two Iterations. By default, duplicates are not filtered from the results.

Parameters:

arg1 - An Iteration containing the first set of elements.

arg2 - An Iteration containing the second set of elements.

IntersectIteration

public IntersectIteration(Iteration<? extends E,? extends X> arg1,
                          Iteration<? extends E,? extends X> arg2,
                          boolean distinct)

Creates a new IntersectIteration that returns the intersection of the results of two Iterations.

Parameters:

arg1 - An Iteration containing the first set of elements.

arg2 - An Iteration containing the second set of elements.

distinct - Flag indicating whether duplicate elements should be filtered from the result.

Method Detail

accept

protected boolean accept(E object)
                  throws X extends Exception

Returns true if the object is in the set of elements of the second argument.

Specified by:

accept in class FilterIteration<E,X extends Exception>

Parameters:

object - The object to be tested.

Returns:

true if the object should be returned, false otherwise.

Throws:

X

X extends Exception

handleClose

protected void handleClose()
                    throws X extends Exception

Description copied from class: IterationWrapper

Closed this Iteration and also closes the wrapped Iteration if it is a CloseableIteration.

Overrides:

handleClose in class FilterIteration<E,X extends Exception>

Throws:

X

X extends Exception