public static boolean checkSignature(String signature , String timestamp , String nonce){
		String[] arr = new String[]{
				token , timestamp , nonce
		};
		Arrays.sort(arr);
		StringBuilder content = new StringBuilder();
		for(int i=0;i<arr.length;i++){
			content.append(arr[i]);
		}
		MessageDigest md = null;
		String tmpStr = null;
		
		try {
			md = MessageDigest.getInstance("SHA-1");
			byte[] digest = md.digest(content.toString().getBytes());
			tmpStr = byteToStr(digest);
		} catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		content = null;
		return tmpStr != null ? tmpStr.equals(signature.toUpperCase()) : false;
	}