This contains the example Java program showing how file locking is
provided. This example has been modified somewhat from the text in that
the file being locked is passed on the command line.

Also, the thread produces an output message before trying to acquire 
the lock and after it has released it. Furthermore, once it has acquired
the lock, thread waits ten seconds before releasing it.

On systems supporting either manadatory (i.e. Windows) or advisory 
(i.e. UNIX) locking, running two copies of this program illustrates how
the Java file locking API works. 

Another test is to first run the Java program to acquire
the file lock. Next, try opening the locked file  using a standard text editor
or word processor. Compare the different behavior on mandatory and advisory
systems.
