import java.awt.Dimension;
import java.awt.Toolkit;
import javax.swing.JFrame;
public class SizingWindowswithToolkit {
public static void main(String[] args) {
JFrame aWindow = new JFrame("This is the Window Title");
Toolkit theKit = aWindow.getToolkit();
Dimension wndSize = theKit.getScreenSize();
aWindow.setBounds(wndSize.width / 4, wndSize.height / 4, // Position
wndSize.width / 2, wndSize.height / 2); // Size
aWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
aWindow.setVisible(true);
}
}