As the earlier post suggests - you cannot submit
Java objects via HTTP form posts. Once you've displayed the results in a browser, it does not know anything about Java objects. All HTTP can do is send text - this is why Web Services (in their most common form) use XML. If it was easy to send binary encodings over standard HTTP - Web Services would be different (you'd end up with something like RMI) because binary is much more efficient than plain text.
Basically you must either uses the Session object (essentially a HashMap that maintains its values for a given user's session - where the
J2EE container manages a session, usually via cookie for you automatically) OR you must persist the state yourself - for example as hidden form fields or cookies or storing in a database (where you store the record key in a cookie).
Usually people go with Session objects unless you know you're dealing with very large amounts of data in an object.
Mark