public void berechneRestzeit(Date end) {
		Date now = new Date(); //current date
		long diff = end.getTime() - now.getTime(); //milliseconds
		long days = diff/(1000*60*60*24);
		long hours = (diff-days*1000*60*60*24)/(1000*60*60);
		long minutes = (diff-days*1000*60*60*24-hours*1000*60*60)/(1000*60);
		String rest = "";
		if(days < 0 || hours < 0 || minutes < 0){
			rest = "0m";
		}
		else{
			if(days == 0){
				if(hours == 0)
					rest = minutes + "m";
				else
					rest = hours + "h" + minutes + "m";
			}else{
				rest = days + "d" + hours + "h" + minutes + "m";
			}
		}
		setRestzeit(rest);
	}