[aspectj-users] AspectJ and metadata

[Adrian Powell <apowell@xxxxxxxxxx>]

In the "Eclipse AspectJ" book,
the integration between Hibernate and AspectJ came up several times, both
in the initial example and then towards the end of the book where it is
refactored to use Spring.  The example raises an interesting design
philosophy question which I've been trying to hash out with collegues,
but we haven't come up with any clinching arguments.

The problem is this: in our applications,
we have been using XDoclet to add Hibernate information into our Java source
files.  The goal is ostensibly to centralize the functions of a class
into one location so that its functionality is clear and easier to maintain.
 On the other hand, the AspectJ example goes the opposite direction
and tries to separate out all of the Hibernate functionality.  In
the XDoclet solution, we have a single .java file and an ant script which
will build the .hbm.xml files.  In the AspectJ solution, we have a
.java file, a .aj file, and a hand-coded .hbm.xml file.  I recognize
that the AspectJ example is just that, an example, but it does have some
interesting advantages.  With metadata entering Java 5, I think the
issue of how to decompose and modularize a solution will continue to gain
attention.

So my question for the group is: do
you prefer to separate out these sorts of concerns with AspectJ, or unify
them with XDoclet or metadata?  


cheers,
-adrian.
--
Adrian Powell
Centre for IBM e-Business Innovation :: Vancouver
apowell@xxxxxxxxxx / 604-297-3194