public dbMaintainDialog(MainFrame mainFrame) {
        super(mainFrame,true);
        setTitle("ݿά");

        JPanel contentPanel=new JPanel();
        this.setContentPane(contentPanel);

        final JLabel tipsJbl=new JLabel("");

        JTextArea backupText=new JTextArea("ݡťdbļɱļdb.backup");
        backupText.setEditable(false);
        JButton backBtn=new JButton("");
        backBtn.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {        //Ӽ
                String srcFile;
                String destPath;
                srcFile="PIA/data/db.mdb";
                destPath="PIA/data/db.backup";
                DB.close();     //رݿ
                FileCopy(srcFile,destPath);     //ļ
                DB.open();     //ݿ
                tipsJbl.setText("ݳɹ");
            }
        });

        JTextArea recoverText=new JTextArea("ԭťdbļµdb.backupԭݿ⣬粻ڱļܻԭ");
        recoverText.setEditable(false);
        JButton recoverBtn=new JButton("ԭ");
        recoverBtn.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String srcFile;
                String destPath;
                srcFile="PIA/data/db.backup";
                destPath="PIA/data/db.mdb";

                File file=new File(srcFile);
                if(file.exists()){          //ⱸļǷ
                    DB.close();     //رݿ
                    FileCopy(srcFile,destPath);     //ļ
                    DB.open();     //ݿ
                    tipsJbl.setText("ԭɹ");
                }
                else{
                    JOptionPane.showMessageDialog(null,"ļڣȱݣ");
                }

            }
        });

        contentPanel.add(backupText);
        contentPanel.add(backBtn);
        contentPanel.add(recoverText);
        contentPanel.add(recoverBtn);
        contentPanel.add(tipsJbl);

        setSize(600, 200);
        setLocationRelativeTo(null);
        setVisible(true);
    }