public void readRTSItems(String fileName) 
	 {
		try { 
		 this.fileName = fileName;
		 if (!new File(fileName).exists())
		 {	 
			new File(fileName).createNewFile();			   	
			return;
		 }	
		 else {			    
		    ObjectInputStream input = new ObjectInputStream(new FileInputStream(fileName));

            points = (HashMap<String, Location>)input.readObject();
            lines = (HashMap<String, Line>)input.readObject();
            visible = (HashMap<String, Boolean>)input.readObject();
            
            Set<Map.Entry<String, Location>> locSet = points.entrySet();
            for(Map.Entry<String, Location> m: locSet)
            {
            	String locName = m.getKey();
            	busStopList.addItem(locName);
            	busStopListDep.addItem(locName);
            	busStopListDest.addItem(locName);
            }

            Set<Map.Entry<String, Line>> lineSet = lines.entrySet();
            for(Map.Entry<String, Line> m: lineSet)
            {
            	String lineName = m.getKey();
          	    lineList.addItem(lineName);
            }   
            
		 }
		}	 		
		catch(IOException e) { e.printStackTrace(); System.out.println("Problem reading shapes");}
		catch(ClassNotFoundException e) { System.out.println("Class couldn't be loaded when reading Shape and subclass objects");}
	 }