Java tutorial
import java.awt.Dimension; import java.awt.Toolkit; import javax.swing.JFrame; public class Main { public static void main(String args[]) { JFrame frame = new JFrame(); Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); int width = (int) screenSize.getWidth(); int height = (int) screenSize.getHeight(); Dimension newDim = new Dimension(width, height - 40); frame.setSize(newDim); frame.setVisible(true); // FIRST visible = true frame.setResizable(false); // THEN resizable = false frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } }