import java.awt.event.*;
import java.io.*;
import java.nio.channels.*;
import javax.swing.*;
public class Main {
private FileChannel channel;
private FileLock lock;
private boolean blocked;
public Main() {
try {
channel = new RandomAccessFile(new File("MainLock.txt"),
"rw").getChannel();
lock = channel.tryLock();
if (lock == null) {
blocked = true;
}
} catch (Exception e) {
blocked = true;
}
if (!blocked) {
JFrame f = new JFrame();
f.setSize(400, 300);
f.setVisible(true);
f.addWindowListener(new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
exit();
}
});
}
}
protected void exit() {
try {
lock.release();// Release the lock
channel.close();// Close the file
} catch (Exception e) {
e.printStackTrace();
}
System.exit(0);
}
public static void main(String[] args) {
new Main();
}
}
