Java by API/javax.swing/DesktopManager

DesktopManager: maximizeFrame(JInternalFrame f)

  
import java.awt.BorderLayout;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.JLabel;
public class Main {
  public static void main(final String[] args) {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JDesktopPane desktop = new JDesktopPane();
    JInternalFrame internalFrame = new JInternalFrame("Can Do All", true, true, true, true);
    desktop.add(internalFrame);
    internalFrame.setBounds(25, 25, 200, 100);
    JLabel label = new JLabel(internalFrame.getTitle(), JLabel.CENTER);
    internalFrame.add(label, BorderLayout.CENTER);
    internalFrame.setVisible(true);
    desktop.getDesktopManager().maximizeFrame(internalFrame);
    frame.add(desktop, BorderLayout.CENTER);
    frame.setSize(500, 300);
    frame.setVisible(true);
  }
}