Map parameters = new HashMap();
			parameters.put("appId", WeChatPayConfig.appid);
			parameters.put("body", "hehe");
			parameters.put("mch_id", WeChatPayConfig.mch_id);
			parameters.put("nonce_str", "1add1a30ac87aa2db72f57a2375d8fec");
			parameters.put("device_info", WeChatPayConfig.device_info);
			parameters.put("notify_url", WeChatPayConfig.notify_url);
			parameters.put("out_trade_no", "654654654656");// 订单号
			parameters.put("spbill_create_ip", "127.0.0.1");// 用户IP
			parameters.put("total_fee", "1");// 金额
			parameters.put("trade_type", WeChatPayConfig.trade_type);
			parameters.put("product_id", "qwe1324657987989786");
			// 生成签名
			parameters.put("sign",
					WeiXinPayUtil.generateSignature(parameters, WeChatPayConfig.key, SignType.MD5));

返回值：
return_code:FAIL
return_msg:缺少参数