@Override
 public void selectedTabChange(SelectedTabChangeEvent event) {
   final Component tab = event.getTabSheet().getSelectedTab();
   if (tab instanceof HSTab) {
     ((HSTab) tab).fillTable();
   }
 }
  @Override
  public TabSheet createTabs(Object itemId) throws RpcException {
    final TabSheet tabsheet = new TabSheet();
    tabsheet.addSelectedTabChangeListener(this);
    tabsheet.addTab(new GenericForm("pac", session, itemId, "name"), I18N.getText("pac"));
    final HSTab usersTab = new HSTab("user", session, "pac", itemId, "name");
    usersTab.fillTable();
    tabsheet.addTab(usersTab, I18N.getText("user"));
    final HSTab aliasTab = new HSTab("emailalias", session, "pac", itemId, "name");
    tabsheet.addTab(aliasTab, I18N.getText("emailalias"));
    final HSTab domainTab = new HSTab("domain", session, "pac", itemId, "name");
    tabsheet.addTab(domainTab, I18N.getText("domain"));

    final HSTab mysqluserTab = new HSTab("mysqluser", session, "pac", itemId, "name");
    tabsheet.addTab(mysqluserTab, I18N.getText("mysqluser"));
    final HSTab mysqldbTab = new HSTab("mysqldb", session, "pac", itemId, "name");
    tabsheet.addTab(mysqldbTab, I18N.getText("mysqldb"));
    final HSTab postgresqluserTab = new HSTab("postgresqluser", session, "pac", itemId, "name");
    tabsheet.addTab(postgresqluserTab, I18N.getText("postgresqluser"));
    final HSTab postgresqldbTab = new HSTab("postgresqldb", session, "pac", itemId, "name");
    tabsheet.addTab(postgresqldbTab, I18N.getText("postgresqldb"));
    return tabsheet;
  }