org.archive.util.iterator
Class LookaheadIterator<T>

java.lang.Object
  org.archive.util.iterator.LookaheadIterator<T>

All Implemented Interfaces:

java.util.Iterator<T>

Direct Known Subclasses:

LineReadingIterator, TransformingIteratorWrapper

public abstract class LookaheadIterator<T>
extends java.lang.Object
implements java.util.Iterator<T>

Superclass for Iterators which must probe ahead to know if a 'next' exists, and thus have a cached next between a call to hasNext() and next().

Author:

gojomo

Field Summary

protected T

next

Constructor Summary

LookaheadIterator()

Method Summary

boolean	hasNext() Test whether any items remain; loads next item into holding 'next' field.
protected abstract boolean	lookahead() Caches the next item if available.
T	next() Return the next item.
void	remove()

Methods inherited from class java.lang.Object

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

Field Detail

next

protected T next

Constructor Detail

LookaheadIterator

public LookaheadIterator()

Method Detail

hasNext

public boolean hasNext()

Test whether any items remain; loads next item into holding 'next' field.

Specified by:

hasNext in interface java.util.Iterator<T>

See Also:

Iterator.hasNext()

lookahead

protected abstract boolean lookahead()

Caches the next item if available.

Returns:

true if there was a next item to cache, false otherwise

next

public T next()

Return the next item.

Specified by:

next in interface java.util.Iterator<T>

See Also:

Iterator.next()

remove

public void remove()

Specified by:

remove in interface java.util.Iterator<T>