Re: File Locking Question

#Whether or not a lock actually prevents another program from
#accessing the content of the locked region is system-dependent and
#therefore unspecified. The native file-locking facilities of some
#systems are merely advisory, meaning that programs must cooperatively
#observe a known locking protocol in order to guarantee data integrity.
#On other systems native file locks are mandatory, meaning that if one
#program locks a region of a file then other programs are actually
#prevented from accessing that region in a way that would violate the
#lock. On yet other systems, whether native file locks are advisory or
#mandatory is configurable on a per-file basis. To ensure consistent and
#correct behavior across platforms, it is strongly recommended that the
#locks provided by this API be used as if they were advisory locks.

http://java.sun.com/javase/6/docs/api/java/nio/channels/FileLock.html