Servlet mapping: url-pattern for URLs with trailing slash

I have a problem related to the servlet mapping. I have the following in web.xml:

<servlet>
    <servlet-name>HelloWorldServlet</servlet-name>
    <servlet-class>test.HelloWorldServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>HelloWorldServlet</servlet-name>
    <url-pattern>/HelloWorld</url-pattern>
</servlet-mapping>

If I access to http://localhost:<port>/MyApp/HelloWorld the servlet HelloWorldServlet is called.

I also want my servelet to respond to http://localhost:<port>/MyApp/HelloWorld/. How can I achieve this effect? I'm developing with NetBeans but it does not allow me to put a pattern ended with /.