Deploy my project successfully on Tomcat but cannot request. Show 404

I put my project war file into webapps.

And I checked catalina log first. There is no error. And deployed successfully.

And I checked Tomcat manager page. The project is deployed and started.

But when I request like "localhost:8080/MetroDemo/", it shows me a 404 page.

PS: My project can run and request successfully on eclipse through Tomcat, and I use springMVC in my project. And Tomcat Version is 8.0.44, JDK 1.8.