P4Package is a set of java clases for access to P4.  

You can visit the [official P4Package|http://public.perforce.com/public/perforce/api/java/p4package/index.html] the reason that I didn't link directly to the official site from [P4FileProvider.java] is I had to make some modifications to P4Package.

I think that API is a little messy to follow, especially when your coming from the perspective of the simple p4 commandline interface.  Regardless I didn't want to go about writing a bunch of code for p4 access, (lazy like everyone else).  So I used it.  But... I found a bug in FileEntry and added a new method.  I tried to commit my changes back the depot, but sending mail to Perforce they suggested I contact the author David A. Markley and I never got a reply.  So for now [P4FileProvider.java] uses a slightly modified version of p4.jar.  

[P4FileProvider.java] does require the P4Utils.zip file and I made a bunch of changes to those files to fix bugs as well, since P4 at the time (don't recall now) didn't really have a decent API for java access. I tried to submit them back to the repository that p4 had/has set up but the owner/author never repsponded. I'll see if I can get a copy of these src files as well as a .jar file of that build for you as well..