Tomcat启动报错Port 80 required by Tomcat v7.0 Server at localhost is already in use. The server may alre

报错内容：

Port 80 required by Tomcat v7.0 Server at localhost is 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).

 意思为：80端口被占用。

方式一：

stop Tomcat然后重启，可能就不会报错了。

方式二：

win + R输入cmd，进入DOS，输入：

netstat -ano|findstr 80

然后用命令杀死或者进入任务管理器中找到对应PID,结束进程即可。