net.sf.jga.fn.algorithm
Class LookAheadFunctor<T>

java.lang.Object
  net.sf.jga.fn.UnaryFunctor<java.util.Iterator<? extends T>,LookAheadIterator<T>>
      net.sf.jga.fn.algorithm.LookAheadFunctor<T>

All Implemented Interfaces:

java.io.Serializable, Visitable

Direct Known Subclasses:

FindAdjacent, FindMismatch, FindRepeated, FindSequence

public abstract class LookAheadFunctor<T>
extends UnaryFunctor<java.util.Iterator<? extends T>,LookAheadIterator<T>>

Abstract base class for functors that take an input iterator and return a LookAheadIterator. This class provides the ability to prevent excessive iterator wrapping by tracking the identity of the functor that has produced the wrapped iterator, and not re-wrapping an iterator if it was produced by the same object that is currently requesting a wrapped iterator.

Copyright © 2004 David A. Hall

Author:

David A. Hall

See Also:

Serialized Form

Constructor Summary

LookAheadFunctor()

Method Summary

protected LookAheadIterator<T>

wrap(java.util.Iterator<? extends T> iterator, int count) Conditionally wraps the input iterator in a LookAheadIterator for return.

Methods inherited from class net.sf.jga.fn.UnaryFunctor

accept, bind, compose, compose, fn, generate

Methods inherited from class java.lang.Object

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

Constructor Detail

LookAheadFunctor

public LookAheadFunctor()

Method Detail

wrap

protected LookAheadIterator<T> wrap(java.util.Iterator<? extends T> iterator,
                                    int count)

Conditionally wraps the input iterator in a LookAheadIterator for return. Uses a Wrapper to determine if the input iterator is one that this object has already built and returned: if so, then there is no need to wrap it again.