@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");
                }

            }