jtp.frame.vc
Class GraphWalker

java.lang.Object
  |
  +--jtp.frame.vc.GraphWalker

All Implemented Interfaces:

Iterator

Direct Known Subclasses:

BackwardChainingWalker

public abstract class GraphWalker

extends Object

implements Iterator

GraphWalker.java This class walks through the graph of ValueCollections connected with ValueLinks. It keeps a set of visited nodes, preventing cycles. Created: Mon Mar 15 03:18:49 1999

Field Summary

protected Set	history The set of visited nodes.
protected boolean	isNew Set to true if we have just arrived to a node, and it hasn't yet been returned by next().
protected LinkedList	links This is another representation of the path from the starting point of the search to the current node.
protected LinkedList	path The stack of Iterators corresponding to the path from the starting point of the search to the current node.

Constructor Summary

GraphWalker()

Method Summary

protected abstract Object	getCurrent()
LinkedList	getLinkChain()
protected abstract boolean	goDown(Object o)
boolean	hasNext()
Object	next()
void	remove()
void	reset() resets this GraphWalker: clears history, path and links; sets isNew to false.

Methods inherited from class java.lang.Object

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

Field Detail

history

protected Set history

The set of visited nodes.

path

protected LinkedList path

The stack of Iterators corresponding to the path from the starting point of the search to the current node. Every element of this list is an Iterator of edges leading from the corresponding node that have not yet been taken.

links

protected LinkedList links

This is another representation of the path from the starting point of the search to the current node. This list contains the links that constitute the path.

isNew

protected boolean isNew

Set to true if we have just arrived to a node, and it hasn't yet been returned by next().

Constructor Detail

GraphWalker

public GraphWalker()

Method Detail

reset

public void reset()

resets this GraphWalker: clears history, path and links; sets isNew to false.

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator

next

public Object next()

Specified by:

next in interface Iterator

remove

public void remove()

Specified by:

remove in interface Iterator

getLinkChain

public LinkedList getLinkChain()

goDown

protected abstract boolean goDown(Object o)

getCurrent

protected abstract Object getCurrent()