I saw one of the top IDEs at JavaOne has all of
the gang-of-four
design patterns implemented (and some other design
patterns as well).
Adding say a Facade pattern is as simple as
selecting design patterns
-> choosing the pattern name -> going through a
simple wizard which
is extremely simple: it explains what the pattern
is for, and
then asks for the values of one or two parameters.
It then creates
the design pattern classes as necessary.

This might make a good university project -
implementing the design
patterns cleanly in Java; the design patterns are
all well documented so it's just a matter of
java-ifying them and putting
a simple wizard (like the New Class wizard) on them.

Also see the book "Bitter Java", which reportedly
(I haven't read
it -- yet!) contains a number of java-specific
knowledge and
caveats about design patterns implemented in java,
many with
a web-flavor (so while the basic java module needs
to support
the basic design patterns, it might be that other
modules should
add appropriate design patterns for their domains
as well).