I'm new to Jetty, and I tried to run the example for "HelloWorld"

```
public class HelloWorld extends AbstractHandler
{
    public void handle(String target,
                       Request baseRequest,
                       HttpServletRequest request,
                       HttpServletResponse response) 
        throws IOException, ServletException
    {
        response.setContentType("text/html;charset=utf-8");
        response.setStatus(HttpServletResponse.SC_OK);
        baseRequest.setHandled(true);
        response.getWriter().println("<h1>Hello World</h1>");
    }

    public static void main(String[] args) throws Exception
    {
        Server server = new Server(8080);
        server.setHandler(new HelloWorld());

        server.start();
        server.join();
    }
}

```

and the "Hello World" does shows on the JSP page in my localhost:8080. But I'm not able to change any content inside, or even stop the server. What can I do with this?