magicmap-commits

[Florian L. <fle...@us...>]

Update of /cvsroot/magicmap/magicmapserver/src/net/sf/magicmap/server/cache
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv12089/src/net/sf/magicmap/server/cache

Added Files:
	PositionCache.java 
Log Message:
Implementation des Positioning-Caches

--- NEW FILE: PositionCache.java ---
package net.sf.magicmap.server.cache;

import java.util.Collection;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.SortedMap;
import java.util.TreeMap;

import net.sf.magicmap.db.Map;
import net.sf.magicmap.server.dto.PositionDTO;


public class PositionCache extends Hashtable<Map,PositionCacheEntry>{
	
	private static SortedMap timeMap;
	
// Sigleton Hashtable
	private static PositionCache single_positionCache = null;
	
	public static PositionCache getPositionCache(){
		if (single_positionCache == null)
			single_positionCache = new PositionCache();
		return single_positionCache;
	}

	private PositionCache (){
		//TODO: hohle daten aus der Datenbank
	}
	
	private void addMapHashtable(Map map) {
		this.put(map,new PositionCacheEntry());			
	}
	
	private boolean existsMapHashtable(Map map){
		return this.containsKey(map);		
	}
	
	private PositionCacheEntry getMapHashtable(Map map){
		return this.get(map);
	}
	
	public void createOrUpdatePosition(Map map, PositionDTO position){
		if(!existsMapHashtable(map))
			addMapHashtable(map);
		if(getMapHashtable(map).existsPosition(position.getName())){
			getMapHashtable(map).removePosition(position.getName());
		}
		getMapHashtable(map).addPosition(position);
	}
	
	public PositionDTO[] getPositionsForMapSince(Map map,Long time){
		if(!existsMapHashtable(map))
			return new PositionDTO[0];
		return getMapHashtable(map).getPositionsSince(time);
	}
	
	public PositionDTO getPositionForClientOnMap(Map map, String name){
		if(!existsMapHashtable(map))
			return null;
		return getMapHashtable(map).getPosition(name);
		
	}
}

class PositionCacheEntry {
	private Hashtable<String,PositionDTO> positionHash;
	private TreeMap<Long ,String> timeMap;
	
	protected PositionCacheEntry (){
		positionHash = new Hashtable<String,PositionDTO>(40);
		timeMap = new TreeMap<Long ,String>();
	}
	
	protected void addPosition(PositionDTO position){
		positionHash.put(position.getName(),position);
		timeMap.put(position.getLastModified(),position.getName());
	}
	
	protected boolean existsPosition(String name){
		return positionHash.containsKey(name);
	}
	protected PositionDTO getPosition(String name){
		return positionHash.get(name);
	}
	
	protected void removePosition(String name){
		timeMap.remove(positionHash.get(name).getLastModified());
		positionHash.remove(name);
	}
	
	protected PositionDTO[] getPositionsSince(Long time){
		Collection<String> newPositions = timeMap.tailMap(time).values();
		PositionDTO [] positions = new PositionDTO[newPositions.size()];
		Iterator it = newPositions.iterator();
		int i = 0;
		while(it.hasNext()){
			positions[i++] = getPosition((String)it.next());
		}
		return positions;
	}
}