SortedMap<String, String> tunemap = new TreeMap<String, String>();
tunemap.put("appid",params.get("appid"));
tunemap.put("partnerid",params.get("mch_id"));
tunemap.put("prepayid",params.get("prepay_id"));
tunemap.put("package","Sign=WXPay");
tunemap.put("noncestr",params.get("nonce_str"));
tunemap.put("timestamp",String.valueOf(System.currentTimeMillis()/1000));
String tunemapsign = PayCommonUtil.createSign("utf-8", tunemap, key);
tunemap.put("sign", tunemapsign);

我查看了没有错误，签名方式都一样