package meeting;import javax.swing.UIManager;import java.awt.*;public class MeetingMG {  private boolean packFrame = false;  public MeetingMG() {//構(gòu)造體    MeetingMGFrame frame = new MeetingMGFrame();    if (packFrame) {      frame.pack();    }    else {      frame.validate();    }//將窗體放置在屏幕中央    Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();    Dimension frameSize = frame.getSize();    if (frameSize.height > screenSize.height) {      frameSize.height = screenSize.height;    }    if (frameSize.width > screenSize.width) {      frameSize.width = screenSize.width;    }    frame.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);    frame.setVisible(true);  }    public static void main(String[] args) {    try {      UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());    }    catch(Exception e) {      e.printStackTrace();    }    new MeetingMG();      }}