Subversion integration?

Hi all,

I just subscribed to this list. I may have an interest in using subversion in my own project ( A "hobby" J2EE Quality Support System quite underway, which soon will need some way to store sources ). Basically, I'm thinking of using SVN for source code storage as much de-coupled as possible, but join my data with revision delta's/properties and what have you using the revision ID's, my review ID's and my incident ID's.

I'm using J2EE, so something that caught my eye were the HLJava bindings. Are these actively maintained and kept current with the C - libraries?  They seem an excellent starting point, but I need to still investigate whether I really should start from those.

The next question is whether there are advisable or existing points where listener modules can/should be placed ( assuming Apache server has to be used ).

To explain:  If someone commits a revision, I want to catch this event, but probably after the commit has taken place, since I need the revision number ( depending on when this number really is generated ). Probably I only want the revision log message, the person who made the change, the revision number and custom properties for a possible review ID and an incident ID from my database that I retrieve using my GUI. I can find out what really happened to files, etc. by doing a query in subversion later on the revision ID, so I don't need all the data at this point, it would just slow things down. The idea is to automatically issue ( unallocated ) review requests, connect revisions to my incidents/customers/releases/tasks and to be able to flag unreviewed code in reports.

What is the best point in SVN to trap these events, catching the revision number too?  I expect that at this time, I will end up hacking some library somewhere to create a plugin-point there. Also, should it be possible to transact with SVN commits somehow, meaning that if my db update fails on my incident/review tables, the SVN commit does not take place ( or in worst case, can I  roll back the changes?  less optimal due to ACID-ity, but it gets me started :). I don't want to change anything related with the revision, just catch info and pass it on elsewhere.

Thanks for your time,

Gerard