社区版emqx安装后修改登入到dashboard密码 http://ip:18083/

登入地址：http://ip:18083/

修改用户名admin密码为admin

emqx_ctl admins passwd admin admin

emqx官方java示例
https://www.emqx.io/docs/zh/v4.4/development/java.html#paho-java-%E4%BD%BF%E7%94%A8%E7%A4%BA%E4%BE%8B