How to add dynamically appearing navbar to an html page?

I am working on a mobile Web application (Jira Mobile). This application contains a .jsp file, which is load an html page to a container, and another container to the bottom for the navbar. My question is: how can I say to the page that the content of the navbar have to change depending on where I am on the page? The URL is the same every time, because I am using a Java Servlet, this is like localhost:port/...JavaServlet/