org.eclipse.rdf4j.common.iteration

Class MinusIteration<E,X extends Exception>

java.lang.Object

org.eclipse.rdf4j.common.iteration.AbstractCloseableIteration<E,X>

org.eclipse.rdf4j.common.iteration.IterationWrapper<E,X>

org.eclipse.rdf4j.common.iteration.FilterIteration<E,X>

org.eclipse.rdf4j.common.iteration.MinusIteration<E,X>

All Implemented Interfaces:

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

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

An Iteration that returns the results of an Iteration (the left argument) minus the results of another Iteration (the right argument). 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 org.eclipse.rdf4j.common.iteration.IterationWrapper

wrappedIter

Constructor Summary

Constructors

Constructor and Description
MinusIteration(Iteration<? extends E,X> leftArg, Iteration<? extends E,X> rightArg) Creates a new MinusIteration that returns the results of the left argument minus the results of the right argument.
MinusIteration(Iteration<? extends E,X> leftArg, Iteration<? extends E,X> rightArg, boolean distinct) Creates a new MinusIteration that returns the results of the left argument minus the results of the right argument.

Method Summary

Modifier and Type	Method and Description
protected boolean	accept(E object) Tests whether or not the specified object should be returned by this Iteration.
protected void	handleClose() Closes this Iteration and also closes the wrapped Iteration if it is a CloseableIteration.

Methods inherited from class org.eclipse.rdf4j.common.iteration.FilterIteration

hasNext, next

Methods inherited from class org.eclipse.rdf4j.common.iteration.IterationWrapper

remove

Methods inherited from class org.eclipse.rdf4j.common.iteration.AbstractCloseableIteration

close, isClosed

Methods inherited from class java.lang.Object

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

Constructor Detail

MinusIteration

public MinusIteration(Iteration<? extends E,X> leftArg,
                      Iteration<? extends E,X> rightArg)

Creates a new MinusIteration that returns the results of the left argument minus the results of the right argument. By default, duplicates are not filtered from the results.

Parameters:

leftArg - An Iteration containing the main set of elements.

rightArg - An Iteration containing the set of elements that should be filtered from the main set.

MinusIteration

public MinusIteration(Iteration<? extends E,X> leftArg,
                      Iteration<? extends E,X> rightArg,
                      boolean distinct)

Creates a new MinusIteration that returns the results of the left argument minus the results of the right argument.

Parameters:

leftArg - An Iteration containing the main set of elements.

rightArg - An Iteration containing the set of elements that should be filtered from the main set.

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

Method Detail

accept

protected boolean accept(E object)
                  throws X extends Exception

Description copied from class: FilterIteration

Tests whether or not the specified object should be returned by this Iteration. All objects from the wrapped Iteration pass through this method in the same order as they are coming from the wrapped Iteration.

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

Closes 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