Refactoring to Seam by Brian Leonard

The Poll:

The thrust of the talk: take a typical Java EE 5 application (JavaServer Faces -> managed session bean -> entity class -> database) and refactor it to Seam. This is interesting, but we don’t even have any Java EE 5 web apps to refactor, so both the Java EE and the Seam stuff are new to me.

Java EE: lots of config and the syntax looks nasty after Ruby, though a big improvement over J2EE of years past, for sure.

EJB 3 and EE5

  • Dramatic simplification of all bean types
  • POJOs + annotations
  • Dependency injection

You know, I looked around at the audience at this point, and noticed that the room full of big, dumb-looking people. Not a good sign.

OK, here’s what I learned.

JBoss Seam is an application framework for JSF and EJB; it brings them together. Must be good: it has AJAX! Also has improved state management. The presenter showed this at the end and, yeah, this is good.

Seam eliminates the managed bean, reduces the XML and provides “bijection” for stateful components: dynamic, contextual, bidirectional. What? Yeah, I couldn’t figure it out either.

We get a live demo where the presenter troubleshoots various problems. Never a good idea to expect that you’ll work through issues live in presentation. Buzz kill for the audience.

Ahhh, a choice J2EE moment. The framework needs a blank property file, but if it’s not there, you get a cryptic error message that doesn’t mention property files.

We see pattern-matching to look up EJBs. Can’t recall now if that’s Java EE or Seam.

Seam replaces XML with annotations. Good. The more annotations the better I think. Looks like you can inject dependencies via annotations:
@In private User user;

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