Looking for java util similar to diff for comparing expected directory tree to actual in integration test

[James Carpenter]

I am building a maven plugin whose output is a directory structure with
various files.  As part of an integration test (driven by the shitty
plugin), I would like to compare the output structure/files to those of an
expected structure.  I could probably build this up with DirectoryScanner,
but I'm guessing there is something burried in plexus or elsewhere which
already does this for me.  Any suggestions?