Module org.apache.jena.core

Package org.apache.jena.util.iterator

Class FilterIterator<T>

java.lang.Object

org.apache.jena.util.iterator.NiceIterator<T>

org.apache.jena.util.iterator.WrappedIterator<T>

org.apache.jena.util.iterator.FilterIterator<T>

All Implemented Interfaces:

Iterator<T>, IteratorCloseable<T>, Closeable, ClosableIterator<T>, ExtendedIterator<T>

public class FilterIterator<T>
extends WrappedIterator<T>

Creates a sub-Iterator by filtering. This class should not be used directly any more; the subclasses FilterKeepIterator and FilterDropIterator should be used instead.

Constructor Summary

Constructors

Constructor	Description
FilterIterator(Predicate<T> fl, Iterator<T> e)	Initialises a FilterIterator with its filter and base.

Method Summary

Modifier and Type	Method	Description
boolean	hasNext()	Answer true iff there is at least one more acceptable object.
T	next()	Answer the next acceptable object from the base iterator.
void	remove()	Remove the current member from the underlying iterator.

Methods inherited from class org.apache.jena.util.iterator.WrappedIterator

close, close, create, createIteratorIterator, createNoRemove, forTestingOnly_getBase, ofStream

Methods inherited from class org.apache.jena.util.iterator.NiceIterator

andThen, andThen, asList, asSet, emptyIterator, filterDrop, filterKeep, mapWith, removeNext, toList, toSet

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.jena.util.iterator.ExtendedIterator

forEach, nextOptional

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Details

FilterIterator

public FilterIterator(Predicate<T> fl,
 Iterator<T> e)

Initialises a FilterIterator with its filter and base.

Parameters:

fl - An object is included if it is accepted by this Filter.

e - The base Iterator.

Method Details

hasNext

public boolean hasNext()

Answer true iff there is at least one more acceptable object. [Stores reference into current, sets canRemove false; answer preserved in `hasCurrent`]

Specified by:

hasNext in interface Iterator<T>

Overrides:

hasNext in class WrappedIterator<T>

remove

public void remove()

Remove the current member from the underlying iterator. Legal only after a .next() but before any subsequent .hasNext(), because that may advance the underlying iterator.

Specified by:

remove in interface Iterator<T>

Overrides:

remove in class WrappedIterator<T>

next

public T next()

Answer the next acceptable object from the base iterator. The redundant test of `hasCurrent` appears to make a detectable speed difference. Crazy.

Specified by:

next in interface Iterator<T>

Overrides:

next in class WrappedIterator<T>