// gracefull shutdown
 public void shutdown() {
   Utils.logMessage(this, Severity.WARN, "system shutdown requested.");
   try {
     connPool.closeAllConnections();
   } catch (SQLException e) {
     Utils.logMessage(this, Severity.ERROR, "sql error returned from pool : " + e.getMessage());
   }
   Utils.logMessage(this, Severity.INFO, "system gracefully shutdown.");
   System.exit(0);
 }
  // global authentication method. depends on the ClientType
  public CouponClientFacade login(String name, String password, ClientType clientType) {
    Utils.logMessage(this, Severity.DEBUG, clientType + " login invoked with pass = "******"db hash = " + _adminHash);
      Utils.logMessage(this, Severity.DEBUG, "calculated hash = " + md5HashOfPassword);
      if (md5HashOfPassword.equals(_adminHash)) {
        Utils.logMessage(this, Severity.DEBUG, "admin authenticated by md5.");
        // admin auth success, init AdminFacade and passing the DAO's
        AdminFacade adminFacade = new AdminFacade(customerDao, companyDao, couponDao);
        return adminFacade;
      }
      Utils.logMessage(this, Severity.ERROR, "admin authentication failed. md5 not match !");
    }
    // login of Company
    if (clientType == ClientType.COMPANY) {
      // success auth will return the customer ID
      Long companyId = companyDao.login(name, password);
      if (companyId != null && companyId != 0) {
        // construct a customer with those params
        Company company = new Company();
        company.setId(companyId);
        company.setCompName(name);
        company.setPassword(password);
        // create a CustomerFacade, referring to this company
        CompanyFacade companyFacade = new CompanyFacade(company);
        companyFacade.setCompanyDao(companyDao);
        companyFacade.setCouponDao(couponDao);
        return companyFacade;
      }
    }
    // login of Customer
    if (clientType == ClientType.CUSTOMER) {
      // success auth will return the customer ID
      Long customerId = customerDao.login(name, password);
      if (customerId != null && customerId != 0) {
        // construct a customer with those params
        Customer customer = new Customer();
        customer.setId(customerId);
        customer.setCustName(name);
        customer.setPassword(password);
        // create a CustomerFacade
        CustomerFacade customerFacade = new CustomerFacade();
        // customerFacade need to ref that specific customer  ( 1 per client )
        customerFacade.setCustomer(customer);
        // and ref the DAOs ( customer + coupons )
        customerFacade.setCustomerDao(customerDao);
        customerFacade.setCouponDao(couponDao);
        return customerFacade;
      }
    }
    return null;
  }
 // create concrete DAO objects that implements the interfaces
 // using a Factory pattern enable changing the underlying JDBC with
 // a different implementation
 private void createDAOs(ConnPool connPool) {
   DAOFactory.setConnPool(connPool);
   this.customerDao = DAOFactory.getCustomerDaoInstance();
   this.companyDao = DAOFactory.getCompanyDaoInstance();
   this.couponDao = DAOFactory.getCouponDaoInstance();
   Utils.logMessage(this, Severity.INFO, "3 DAO objects created.");
 }
 // will start cleaner thread ( at c'tor , or after user stoped it manually )
 public void startTimer() {
   // start daily thread to clean old coupons
   Utils.logMessage(
       this,
       Severity.INFO,
       "Thread scheduler started. interval = " + _threadIntervalMinutes + " minutes.");
   timer = new Timer();
   // 60000 msec = 1 min
   // minutes of timer specified in cs.properties file
   timer.scheduleAtFixedRate(
       new DailyCouponExpirationTask(couponDao), 30, (_threadIntervalMinutes * 60000));
 }
  // private c'tor 'hides' the public default one. CouponSystem is a singleton
  private CouponSystemJFrame() {
    // load sys params from properties file
    Utils.logMessage(this, Severity.INFO, "Coupon system created.");

    // NOT IN USE in a web-coupon system. ( see method doc )
    // Utils.sysparam already set by a LoaderServlet
    //
    // Utils.loadSystemParameters();
    sysParams = Utils.getSystemParameters();
    _systemName = sysParams.get("SYSTEM_NAME");
    _adminHash = sysParams.get("ADMIN_HASH");
    _lookAndFeelTemplate = sysParams.get("LOOK_AND_FEEL_TEMPLATE");
    _threadEnabled = Boolean.parseBoolean(sysParams.get("THREAD_ENABLED"));
    _threadIntervalMinutes = Integer.parseInt(sysParams.get("THREAD_INTERVAL_MINUTES"));
    _loggingEnabled = Boolean.parseBoolean(sysParams.get("LOGGING_ENABLED"));
    Utils.setLoggingEnabled(_loggingEnabled);
    Utils.logMessage(
        this, Severity.DEBUG, "hashmap assigned to local vars, configuration applied.");

    setTitle("Coupon System : " + _systemName);
    setResizable(false);
    try {
      UIManager.setLookAndFeel(_lookAndFeelTemplate);
    } catch (ClassNotFoundException
        | InstantiationException
        | IllegalAccessException
        | UnsupportedLookAndFeelException e) {
      Utils.logMessage(this, Severity.PANIC, "cannot load LookAndFeel template. exiting...");
      e.printStackTrace();
      // System.exit(0);
    }

    // load this JFrame only after initialization from properties file.
    this.setVisible(true);

    // Main app CANNOT be closed with 'x' , must press on the 'shutdown'
    // buttong for gracefull shutdown.
    setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
    setBounds(100, 100, 785, 380);
    contentPane = new JPanel();
    contentPane.setLayout(null);
    setContentPane(contentPane);

    btnLogin = new JButton("Login");
    btnLogin.addActionListener(this);
    btnLogin.setBounds(659, 253, 98, 79);
    contentPane.add(btnLogin);

    listSysParams = new JList<Entry<String, String>>();
    listSysParams.setBorder(new LineBorder(new Color(0, 0, 0)));
    listSysParams.setFont(new Font("Consolas", Font.PLAIN, 14));
    listSysParams.setEnabled(false);
    listSysParams.setBounds(20, 11, 737, 219);
    contentPane.add(listSysParams);

    // a model is needed for JTable
    DefaultListModel<Entry<String, String>> model = new DefaultListModel<Entry<String, String>>();
    listSysParams.setModel(model);

    JPanel panelSystem = new JPanel();
    panelSystem.setBorder(new LineBorder(new Color(0, 0, 0)));
    panelSystem.setLayout(null);
    panelSystem.setBounds(20, 253, 428, 79);
    contentPane.add(panelSystem);

    btnShutdown = new JButton("Shutdown system");
    btnShutdown.setForeground(Color.RED);
    btnShutdown.setBounds(20, 36, 181, 23);
    panelSystem.add(btnShutdown);

    btnThread = new JButton("Stop cleaner thread");
    btnThread.addActionListener(this);
    btnThread.setForeground(Color.RED);
    btnThread.setBounds(224, 36, 181, 23);
    panelSystem.add(btnThread);

    JLabel lblSys =
        new JLabel(
            "Coupon system running on : "
                + System.getProperty("os.name")
                + " / [version-"
                + System.getProperty("os.version")
                + "].");
    lblSys.setBounds(20, 11, 369, 14);
    panelSystem.add(lblSys);
    btnShutdown.addActionListener(
        new ActionListener() {
          public void actionPerformed(ActionEvent arg0) {
            // calling for gracefull shutdown
            shutdown();
          }
        });

    // get a Set of Entries from all KVP in Map
    Set<Entry<String, String>> entries = sysParams.entrySet();
    for (Entry<String, String> entry : entries) {
      model.addElement(entry);
    }

    // get/create the connection pool
    connPool = ConnPool.getInstance();

    // pass it to DAO's
    createDAOs(connPool);

    if (_threadEnabled) {
      // start the daily cleaner thread
      startTimer();
    }
  }
 // stop the cleaner thread
 public void stopTimer() {
   timer.cancel();
   Utils.logMessage(this, Severity.INFO, "Thread stopped by user request.");
 }