使用存储在浏览器JAVA中的cookie连接服务器时出现服务器错误400

Question

URL url = new URL("url");

URLConnection conn = url.openConnection();

// conn.setRequestMethod("GET");
String mycookie = "value; JNAT=value; "
                + "LtpaToken2=value";

conn.setRequestProperty("Cookie", mycookie);

conn.connect();