case CUSTOMER:
window = windows.get(windowEnum);
if (window == null) {
CustomerManager customerManager=(CustomerManager)ModelUtil.getBean(CustomerManager.MANAGER_NAME);
viewer = new OverviewView<Customer, CustomerModel>(
new CustomersViewHandler(login,customerManager));
viewers.put(windowEnum, viewer);
}
break;
case ORDER:
window = windows.get(windowEnum);