Hi there,
Don't you think that Head First Design Patterns pre-requires knowledge of J2EE ( JSP , Servlet )
No, definitely not, the book explains very well what the
original gang of 4 patterns are and give indications of how
to implement the prescribed design. It does not require
J2EE knowledge.
The book is not enough though for IBM-486, because you will need
to study in detail UML, for which you need the other two books
I mentioned. 'UML distilled' for UML the diagramming techniques
and 'Applying UML and patters' for the iterative development process.
Personally HF Design Patterns would make studying easier, because
the Larman book is a good but quite dry book, but you definitely need
it since it covers a broad range of topics you will see in the exam.
Cheers,
Gian