Enable Cross-platform File Locking with a Lock Server

JDK 1.4 adds a number of advanced features related to I/O and filesystems. The more advanced I/O features are often non-portable or only partially portable. File locking is one of these features. While most operating systems provide some form of file locking, file locking isn't implemented exactly the same way on every platform.

For a general example of file locking in Java, review the following code snippet. It locks the first 10 bytes of a file called "foo.txt":

RandomAccessFile raf =
new RandomAccessFile( "foo.txt", "rw" );
FileChannel fc = raf.getChannel();
FileLock lock = fc.lock( 0, 10, false );