What’s new in JSF 2.0?
Session title: A complete Tour of JSF 2.0
Speakers: Ed Burns – Sun Microsystems, Inc
Martin Marinschek – IRIAN Solutions
My interest in this talk is simple to explain: I used JSF in a really cool project last year, and found it cable but wanting in a number of respects. Lets see if the problems have been addressed…
The speakers begin with quite a few words about how the JSR was the result of a community effort. Then note that JSF 2.0 doubles the scope and integrates Facelets.
And the new features are…
- Composite components. To a large extent the philosophy is the same as for rails with pay as you go complexity. Goal was to enable true abstractions. Makes heavy use of naming conventions to reduce verbosity. Composite components builds on top of resources and facelets. Nice to know: Mojarra supports Groovy.
- AJAX support inspired by RichFaces, IceFaces, DynamicFaces, ADF Faces. Enables AJAX elements to be specified decleratively or programmatically.
- Partial state saving. Biggest problem for performance to-date was the size of the state. Everything was a state and every request was a post. Pre-view state size is now 25% less than prior to 2.0.
- View parameters. Inspired by Page Parameters from Jboss Seam. Provides a way to map requests parameters to special components within the view. Reduces the need to redeclare all the params across all the pages in the app. I had this problem in the aforementioned app and am glad to hear this issue has been addressed!!!
- System Events. Inspired by Dtrace, influenced by JSFTemplating. This is a publish/subscribe event bus for the JSF app. A suite of events is provided. The list may be extended.
- Resources mechanism is now standardised. Separate Filter or Servlet is now no longer necessary. Resources are now logically related to components. Full “library” support (whatever that means), I18N, versioning,
- Behaviours enabled you to attach a behaviour to a component in a way which I didn’t quite understand.
- Navigation enables pages to be bookmarked. Uses the View Parameters feature to ensure params are validated before rendering the page. Implicit Navigation enables pages to be bookmarked.
- Exception Handler enables a single point of failure handling to be defined for a given app.
- Validation is integrated with JSR303 Bean Validation
- New Scopes have been defined: “conversation” (enables wizard-type functionality); “Flash” inspired by Ruby on Rails, which is used in Master-Detail situations; …
- FacesConcext used during startup/shutdown eases the business of keeping things tidy.
I may have missed one or two points during this rather information-intense session. Nevertheless interesting stuff. Big take-home: JSF2.0 appears far easier to use than its predecessor. It’s also much bigger.
Conclusion: Valuable information, competently presented.
Having been asked 2-3 times at Jazoon about my JSF experience. I now have the impression that interest in JSF is pretty high – and growing. I’d have to go back and look at my notes about the project to see what we could have done better using these new features.
