问腾讯云支付使用java HttpsURLConnection 调用https api 连接错误？

URL url = new URL(cloud_scan_code_pay_url);

con = (HttpsURLConnection) url.openConnection();

con.setSSLSocketFactory(ssf);

con.setDoInput(true);

con.setDoOutput(true);

con.setUseCaches(false);

/* 设置传送的method=POST */

con.setRequestMethod("POST");

con.setRequestProperty("charset", "UTF-8");

con.setRequestProperty("content-type", "application/json");

// ------- 下面出错 java.net.SocketException: Connection reset

DataOutputStream ds = new DataOutputStream(con.getOutputStream());