docs: public static SandboxSignkey sandboxnewPayGetsignkey(String mch_id,String key){
  		MchBaseResult mchBaseResult = new MchBaseResult();
  		mchBaseResult.setMch_id(mch_id);
  		mchBaseResult.setNonce_str(UUID.randomUUID().toString().replace("-", ""));
  		Map<String,String> map = MapUtil.objectToMap(mchBaseResult);
  		String sign = SignatureUtil.generateSign(map,mchBaseResult.getSign_type(),key);
  		mchBaseResult.setSign(sign);
  		String closeorderXML = XMLConverUtil.convertToXML(mchBaseResult);
  		HttpUriRequest httpUriRequest = RequestBuilder.post()
  				.setHeader(xmlHeader)
  				.setUri(MCH_URI + "/sandboxnew/pay/getsignkey")
  				.setEntity(new StringEntity(closeorderXML,Charset.forName("utf-8")))
  				.build();
  		return LocalHttpClient.executeXmlResult(httpUriRequest, SandboxSignkey.class, mchBaseResult.getSign_type(), key);
  	}