While maintenance documents user interfaces are built from data dictionary configuration, creating the web layer for transactional documents is a bit more complex. Thankfully, there are ways to extend the KFS provided framework so that we, as programmers, really concentrate more on the business logic of the page (though for those of us longing to leave business logic behind for a moment and just write some good, old-fashioned HTML...well, there's definitely opportunities for that as well).
KFS is delivered as a normal web application - it works entirely through HTML forms with the occasional PDF report. As such, KFS sits on top of a Java web framework, namely Struts. There are several helpful books out there on Struts; it was one of the earliest Model-View-Controller frameworks used widely in Java, and unlike earlier predecessors, it didn't use session state nearly as extensively, allowing for more pooling of common objects. In terms of KFS, we really just need to concentrate on creating Form for our document, creating one or (much more rarely) more Actions for our document, creating a Struts mapping, and then creating the actual JSP page which is the view. We'll look at how to do each of these in turn:
- Creating the Form
- Creating the Action
- Using JSP Pages