net.sf.mmm.util.collection.base
Class FilteredIterator<E>

java.lang.Object
  net.sf.mmm.util.collection.base.AbstractIterator<E>
      net.sf.mmm.util.collection.base.FilteredIterator<E>

Type Parameters:

E - is the generic type of the iterated elements.

All Implemented Interfaces:

Iterator<E>

public class FilteredIterator<E>
extends AbstractIterator<E>

This is an implementation of an Iterator that adapts another Iterator but only iterates the elements that are accepted by a given Filter.
ATTENTION:
According to the design of the Iterator interface, it is NOT possible to implement the AbstractIterator.remove() method properly here. The method AbstractIterator.hasNext() has to step forward in the adapted Iterator and a call of AbstractIterator.remove() would cause unintended and unpredictable results after AbstractIterator.hasNext() has been called. To prevent damage AbstractIterator.remove() will always throw an UnsupportedOperationException.

Since:

2.0.0

Author:

Joerg Hohwiller (hohwille at users.sourceforge.net)

Field Summary

private Iterator<E>	delegate The actual iterator instance to adapt.
private Filter<E>	filter

Constructor Summary

FilteredIterator(Iterator<E> delegate, Filter<E> filter)
The constructor.

Method Summary

protected E

findNext() This method tries to find the next element.

Methods inherited from class net.sf.mmm.util.collection.base.AbstractIterator

findFirst, hasNext, next, remove

Methods inherited from class java.lang.Object

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

Field Detail

delegate

private final Iterator<E> delegate

The actual iterator instance to adapt.

filter

private final Filter<E> filter

See Also:

findNext()

Constructor Detail

FilteredIterator

public FilteredIterator(Iterator<E> delegate,
                        Filter<E> filter)

The constructor.

Parameters:

delegate - is the Iterator to adapt.

filter - is the Filter that filters the iterated elements.

Method Detail

findNext

protected E findNext()

This method tries to find the next element.

Specified by:

findNext in class AbstractIterator<E>

Returns:

the next element or null if done.