为什么运行jsp总是提示tomcat端口被占用，修改端口号，运行jsp还是提示端口被占用？

错误提示：Several ports (8020, 8033, 8022) required by Tomcat v9.0 Server at localhost are already in use. The server may already be running in another process, or a system process may be using the port. To start this server you will need to stop the other process or change the port number(s).

说明：1.版本：myeclipse2018

2.tomcat版本：9.0

3.tomcat可以正常启动，主页也可以正常打开