Question

I am used to work in Struts Framework. The things there are pretty straight forward. The Action classes use the information received from Action Form (which represented a main entity in my project) classes and then they continue their work calling different methods from some Service Classes of some sort.

Now I’m trying to learn JSF but I can’t understand the exact logic which sits behind this framework. I red some tutorials and followed some examples but they all focus on the request processing life cycle and they use managed beans and backing beans (one for each page) which handle validations, database updates and so on. No action handling of any sort.

I red hear in another post that struts is an Action Framework while JSF is a Component Framework but it seems to me that JSF is a little bit more messy than Struts.

Am I missing something in this whole JSF structure?

Answer 1

they use managed beans and backing beans (one for each page) which handle validations, database updates and so on. No action handling of any sort.

It are those methods which are bound as action attribute of <h:commandLink> and <h:commandButton> which are the real action methods.

E.g.

<h:form>
    <h:inputText id="foo" value="#{bean.foo}" required="true" />
    <h:message for="foo" />
    <h:commandButton value="Submit" action="#{bean.submit}" />
</h:form>

with

@ManagedBean
@RequestScoped
public class Bean {

    private String foo;

    public void submit() {
        // Here, you're inside the action method!
        // Save foo in DB or something: someService.save(foo);
        // Navigate to a different view if necessary.
    }

    // Getter+setter.
}

Note that validation is supposed to be done by Validator classes, not in action methods.

See also:

• Our JSF wiki page
• Design Patterns web based applications (some info about action vs component based)
• What are the main disadvantages of Java Server Faces 2.0?