heuristischgreedysearch.java

puzzle game with java.very good !

/*
 * Created on 9-okt-2004
 *
 * To change the template for this generated file go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
package logic;


import java.util.ArrayList;
import java.util.Iterator;
import java.util.TreeSet;



/**
 * @author gebruiker
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
public class HeuristischGreedySearch extends ProbleemOplosser {
	private TreeSet open;
	private ArrayList closed;
	//private LinkedList closed = new LinkedList();
	
	public SpeelBordToestand getOplossing(SpeelBordToestand start, SpeelBordToestand doel)
	{
		//TODO
		this.clearLists();
		open = new TreeSet(new ManhattanComparator(doel));
		closed = new ArrayList();
		solutionFinderStarted();
		
		open.add(start.clone());
		
		while(open.size() > 0)//zolang de set knopen bevat
		{
			SpeelBordToestand teExpanderen = (SpeelBordToestand)open.first();
			//System.out.println("uitkomst heuristische methode: " + teExpanderen.getManhattanAfstandTot(doel));
			
			Iterator iterator = teExpanderen.getSuccessors().iterator();
			while(iterator.hasNext())
			{
				intNumberOfNodesExpanded++;
				
				Object obj = iterator.next();
				
				if(doel.equals(obj))
				{
					createSolutionList((SpeelBordToestand)obj);
					return getFirst();
				}
					
				if(!closed.contains(obj) && !open.contains(obj))//als deze toestand nog niet voorkomt bij de closed
				{
					open.add(obj);//voeg elke successor toe aan de SET. => automatisch geordend.
				}
			}
			closed.add(teExpanderen);
			open.remove(teExpanderen);
			
		}
		return doel;
	}
	protected void clearLists()
	{
		super.clearLists();
		if(open != null)
			open.clear();
		if(closed != null)
			closed.clear();
	}
}