java - Select webapp start up page based on domain name -

how select start page of tomcat 7 webapp?

there 2 page in webapp , want select based on domain name. example

if admin.foo.com show admin.jsp

if user.foo.com show user.jsp

and if foo.com show index.jsp

you have build logic filter or servlet in webapplication. basically, use httpservletrequest.getrequesturl() parse out subomain of request, , redirect visitor appropriate page.