public static void findSimilairSongsDecisionTree(Collection<String> tags, Lied song){
			ArrayList<Lied> liedjes = new ArrayList<Lied>();
			ArrayList<Lied> tagLiedjes;	
	
			for(String tagName : tags)
			{
				Iterator<Tag> i = Tag.search(tagName, apiKey).iterator();
				Tag tag = i.next();
				while(!tag.getName().equals(tagName) && i.hasNext())
				{
					Tag dummy = i.next();
					if(dummy.getName().equals(tagName))
						tag = dummy;
				}
				try{
					tagLiedjes = lastFM.getTopTracks(tag);
				} catch(Exception e){
					//System.out.println(tag.getName());
					tagLiedjes = new ArrayList<Lied>();
				}
				for(Lied liedje : tagLiedjes)
				{				
					liedjes.add(liedje);
				}
			}
	
			//opbouw v/d decision tree
			Iterator<String> i = tags.iterator();
			DTreeNode prev = new DTreeNode(i.next(), song);
			DTreeNode next;
			DTreeNode root = new DTreeNode(i.next(), prev, song);;
			while(i.hasNext())
			{
				next = root;
				root = new DTreeNode(i.next(), prev,  song);
				prev = next;
			}
	
			//vind 10 meest vergelijkbare liedjes
			ArrayList<Lied> result = root.classify(liedjes, 10);
			gui.setFeedbackPanel(result);		
		}