Java tutorial
import java.awt.Dimension; import javax.swing.JFrame; import javax.swing.JRootPane; public class Main extends JFrame { public Main() { setTitle("like JDialog"); setSize(new Dimension(500, 100)); setUndecorated(true); setResizable(false); getRootPane().setWindowDecorationStyle(JRootPane.PLAIN_DIALOG); setLocationRelativeTo(null); setDefaultCloseOperation(EXIT_ON_CLOSE); } public static void main(String[] args) { new Main().setVisible(true); } }