Tip: The following post has a simple example on form/workflow/Java file: http://www.topicobserver.com/blog/sun-idm/2008/custom-forms-and-view-handlers-in-sun-identity-management-80/ . Be careful, there are different ways to call a java method depends on if it is static or not. Of course, the rule of Java is try to make all method as static as possible.
Tip: The Java API document from SunIDM is almost useless. Another way to approach those blackboxes is decompile all the idm*.jar files. I found that the JD-GUI Java Decompiler is easy to use. http://java.decompiler.free.fr/?q=jdgui
Tip: Dump of the context in workflow is very useful since the debug interface is hard to go over every attribute.
Resources:
1. general info to start: http://www.sun.com/software/products/identity_mgr/faqs.xml
2. Forums: http://forums.sun.com/forum.jspa?forumID=764&start=0
3. Xpress language: http://docs.sun.com/source/819-4485/XPRESS.html
