Integrating spring and vaadin - spring

Question

Is it good to integrate Spring and vaadin? I am looking to use vaadin in view layer and spring for my services. So far I am not able to find any neat solution for integration. Is it even a good idea for Production applications like management solutions or ERP?
what could be the design of the application?
How to keep clear separation between application layers?
Issues with Vaadin integration with spring security?
How to manage scope of spring beans?
Also could anyone share the advantages and disadvantages of this integration over spring MVC.

Answer 1

You have a very useful add-on for Vaadin called SpringVaadinIntegration.
You can keep a clean separation very easily with Vaadin, just use Spring #Autowired and services for the data retrieval and modification.
I've used Spring security and I had no problems with Vaadin.
You can manage the scope with the #Scope annotation, with three differents values, if I remember correctly: Singleton (default), Prototype and Session.

Answer 2

Did you consider using Vaadin UIProvider mechanism. This way autowiring in UI is totally transparent.
You can have a look at a really simple example that uses this solution on github: spring-vaadin-example

Answer 3

You don't need any special vaadin addons for spring at all. Just use aspectj and #Configurable annotation along with #Autowired for every component you want to integrate with spring. Like this:
#Configurable(preConstruction = true)
public class LoginUserPasswdDialog extends LoginDialogBase {
static final Logger log = Logger.getLogger(LoginUserPasswdDialog.class);
#Autowired
private AppConfig config;
#Autowired
UserFactory userFactory;
StringBuffer name;
LoggedAction action;
protected Window parent = null;
protected Button ok;
protected Label l;
protected TextField nameText;
protected PasswordField password;
protected CheckBox saveUserPass;
protected final Window w = new Window("");
#SuppressWarnings("serial")
public void create(AbstractComponent component) throws Exception {
parent = component.getWindow();
VerticalLayout v = new VerticalLayout();
v.setSizeFull();
v.setSpacing(true);
l = new Label(
_.getString("LoginUserPasswdDialog.0"), Label.CONTENT_XHTML); //$NON-NLS-1$
l.setSizeFull();
l.addStyleName("centeredLabel");
v.addComponent(l);
HorizontalLayout h = new HorizontalLayout();
h.setMargin(true);
h.setSpacing(true);
nameText = new TextField();
nameText.setWidth("100%");
v.addComponent(nameText);
nameText.focus();
password = new PasswordField();
password.setWidth("100%");
v.addComponent(password);
saveUserPass = new CheckBox(_.getString("LoginUserPasswdDialog.1")); //$NON-NLS-1$
v.addComponent(saveUserPass);
v.setComponentAlignment(saveUserPass, Alignment.MIDDLE_RIGHT);
ok = new Button(_.getString("LoginUserPasswdDialog.2")); //$NON-NLS-1$
ok.setWidth("100px");
ok.setClickShortcut(KeyCode.ENTER);
h.addComponent(ok);
h.setComponentAlignment(ok, Alignment.MIDDLE_CENTER);
v.addComponent(h);
v.setComponentAlignment(h, Alignment.MIDDLE_CENTER);
Cookie nameCookie = CookieUtils.getCookie("username");
Cookie passCookie = CookieUtils.getCookie("password");
if (nameCookie != null && passCookie != null) {
nameText.setValue(nameCookie.getValue());
password.setValue(passCookie.getValue());
saveUserPass.setValue(true);
}
w.setWidth("400px");
w.setCaption(config.getTitle() + _.getString("LoginUserPasswdDialog.4"));
w.setResizable(false);
w.setClosable(false);
w.setModal(true);
w.center();
ok.addListener(new ClickListener() {
public void buttonClick(ClickEvent event) {
String name = (String) nameText.getValue();
String pass = (String) password.getValue();
User u = userFactory.getUser(name, pass);
if (u != null) {
if ((Boolean) saveUserPass.getValue()) {
CookieUtils.makeCookie("username", name);
CookieUtils.makeCookie("password", pass);
} else {
CookieUtils.deleteCookie("username");
CookieUtils.deleteCookie("password");
}
userFactory.updateUser(u);
action.loggedIn(u);
parent.removeWindow(w);
return;
} else {
password.setValue("");
WaresystemsUI.handle
.get()
.getMainWindow()
.showNotification(
"",
_.getString("LoginUserPasswdDialog.3"), Notification.TYPE_ERROR_MESSAGE); //$NON-NLS-1$
return;
}
}
});
w.addComponent(v);
parent.addWindow(w);
}
#Override
public void setAction(LoggedAction loggedAction) {
this.action = loggedAction;
}
}
Of course you need add support to the web.xml:
<!-- SPRING -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath*:META-INF/spring/application-context.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<filter>
<filter-name>requestContextFilter</filter-name>
<filter-class>org.springframework.web.filter.RequestContextFilter</filter-class>
<init-param>
<param-name>threadContextInheritable</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>requestContextFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

Answer 4

Take a look also on Spring UI scope add-on http://vaadin.com/addon/spring-ui-scope
The add-on defines custom Spring scope: UI-scope, which pass well with Vaadin application.
There is also sample application using the scope.