JFrame: setUndecorated(boolean b)
import javax.swing.JFrame; import javax.swing.JRootPane; public class MainClass { public static void main(final String args[]) { JFrame frame = new JFrame("Adornment Example"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setUndecorated(true); frame.getRootPane().setWindowDecorationStyle(JRootPane.FRAME); frame.setSize(300, 100); frame.setVisible(true); } }