Swing JFC Java


            import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Label;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main {
  public static void main(String[] argv) {
    JFrame demo = new JFrame("GridBag demo, to center a component");
    JPanel parentPanel = new JPanel();
    GridBagLayout gridbag = new GridBagLayout();
    GridBagConstraints constraints = new GridBagConstraints();
    constraints.fill = GridBagConstraints.CENTER;
    gridbag.setConstraints(parentPanel, constraints);
    parentPanel.setLayout(gridbag);
    Label centerLabel = new Label(" AAA...");
    parentPanel.add(centerLabel);
    demo.add(parentPanel);
    demo.setSize(500, 500);
    demo.setVisible(true);
  }
}