protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		//΢żǩ
		String signature = request.getParameter("signature");
		//֤ʱ
		String timestamp = request.getParameter("timestamp");
		//֤
		String nonce = request.getParameter("nonce");
		//ַ֤
		String echostr = request.getParameter("echostr");
		
		PrintWriter out = response.getWriter();
		
		//ͨsignature У飬Уɹԭechostrʾɹʧ
		
		if(SignUtil.checkSignature(signature, timestamp, nonce)){
			out.print(echostr);
		}
		out.close();
		
		out = null;
		
	}