您好，我有一个关于Connect to qyapi.weixin.qq.com:443 [qyapi.weixin.qq.com/127.0.1.2] failed: Connection refused: connect]问题 用POSTMAN发送get request access_token没有任何问题，用Python 发送get request access_token没有任何问题，但是我用JAVA 试图发送get request access_token，总是得到错误：java.net.ConnectException: Connection refused: connect 2021-09-09 13:28:02.304 ERROR 25120 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.RuntimeException: org.apache.http.conn.HttpHostConnectException: Connect to qyapi.weixin.qq.com:443 [qyapi.weixin.qq.com/127.0.1.2] failed: Connection refused: connect] with root cause 防火墙已经关了。 请协助，谢谢！