import java.io.File;
import java.io.FileOutputStream;
import java.nio.channels.FileLock;

public class LockTest {
    public static void main (String[] args) throws java.io.IOException {
	File file = File.createTempFile("locktest", null);
	FileOutputStream stream = new FileOutputStream(file, true);
	FileLock lock = stream.getChannel().tryLock();
	System.out.println( "locked " + file.getCanonicalPath()
			  + ": " + lock.toString() );
    }
}