You can use the java.net.URLConnection and java.net.URL classes to open a
standard HTTP connection to the web server. The server then passes this
information to the servlet in the normal way. Basically, the applet  pretends to
be a web browser, and the servlet doesn't know the difference. As far as the
servlet is concerned, the applet is just another HTTP client. See detail from
following URL.
www.j-nine.com/.../Applet2Servlet.html (Applet and
Servlet Communication)
or http://www.jguru.com/faq/view.jsp?EID=157 .