How do I send information and data back and forth between applet and servlet using the HTTP protocol?

Alex Chaffee

Use the standard java.net.URL class, or "roll your own" using java.net.Socket. See the HTTP spec at W3C for more detail.

Note: The servlet cannot initiate this connection! If the servlet needs to asynchronously send a message to the applet, then you must open up a persistent socket using java.net.Socket (on the applet side), and java.net.ServerSocket and Threads (on the server side).