public class yggh extends JFrame{public yggh(){super();final BorderLayout borderLayout=new BorderLayout();setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);borderLayout.setVgap(10);getContentPane().setLayout(borderLayout);setTitle("圖書館管理系統登錄");Toolkit tool=Toolkit.getDefaultToolkit();Dimension screenSize=tool.getScreenSize();setSize(285,194);setLocation((screenSize.width-getWidth())/2,(screenSize.height - getHeight())/2 - 100);final JPanel mainPanel=new JPanel();mainPanel.setLayout(new BorderLayout());mainPanel.setBorder(new EmptyBorder(0, 0, 0, 0));getContentPane().add(mainPanel);final JLabel imageLabel=new JLabel();ImageIcon loginIcon=CreatecdIcon.add("login.jpg")\imageLabel.setIcon(loginIcon);imageLabel.setOpaque(true);imageLabel.setBackground(Color.GREEN);imageLabel.setPreferredSize(new Dimension(260,60));mainPanel.add(imageLabel,BorderLayout.NORTH);final JPanel centerPanel=new JPanel();final GridLayout gridLayout=new GridLayout(2,2);gridLayout.setHgap(5);gridLayout.setVgap(20);centerPanel.setLayout(gridLayout);mainPanel.add(centerPanel);final JLabel ueserNamelabel=new JLabel();}}public static void main(String[]){}