@RequestMapping(value = "/calculationUsage", method = RequestMethod.GET)
	@ResponseBody
	public String calculationCost(@RequestParam long startId,
			@RequestParam long endId, @RequestParam long startTime,
			@RequestParam long endTime) {
		Timestamp starTimestamp=new Timestamp(startTime);
		Timestamp endTimestamp=new Timestamp(endTime);
		String string="";
		try {
			Class.forName("org.apache.phoenix.jdbc.PhoenixDriver");
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
		try {
			ArrayList<RealTimePrice> priceList;
				priceList = getPriceList(getLastUpdatePrice(starTimestamp),
						endTimestamp);
			string = calCost(starTimestamp, endTimestamp, startId, endId, priceList);
			Date date=new Date();
			System.out.println(date.getTime());
			return string;
		} catch (InterruptedException e) {
			e.printStackTrace();
			return "false";
		} catch (ExecutionException e) {
			e.printStackTrace();
			return "false";
		}catch (SQLException e) {
			e.printStackTrace();
			return "false";
		}
		
	}