I think you might be a little unclear on the reason for using the Java support, and the usage.
The Java object support in PHP4 is to treat existing Java objects (Beans in most real world cases.) For the most part, these are really java applications (or parts of them), which are fully functional without PHP. A Java object is a Java object...written in Java. There is nothing special about a java object which is called by php, instead of a Java application/serverlet/jsp page, etc.
What you seem like you are asking for is help with the Java language itself. php.net is definitely not the best place to get Java help. Unfortunately, I don't know any good java web sites off the top of my head. I have sliced up dead trees lying around my office I use for that information.
-Pete