David Chappell has a good post on it.
Anyway, SCA is way better then JBI. For starters, it is platform independent and IBM and BEA are both behind it. Man it must suck to be Sun these days. I agree with David that SCA is not w/o politics. Basically, IBM and BEA are coming to wrestle the JCP process out of their hands and start to take control of the future. Makes sense in a lot of ways. Anyway, I don't really care about that crap.
SCA is like M$ WCF/Indigo but for Java. Good stuff, now we are making some progress. There is already an Apache impl underway (Apache Tuscany).
So I looked at the SCA Whitepaper. Didn't see anything that made me writhe on the floor like when I looked at JBI the first time.
Also, happily WSDL/SOAP doesn't appear to be mandated on the wire. Yippee! I'd also agree with David, that this doesn't look real good for J2EE / app centric model. Thank goodness, there is a way out. There is a REST binding as well, but I doubt it will meet the requirements of purists. Really more of a POX binding. Good enough for me. I wouldn't be surprised if this is how WSDL/SOAP eventually gets deprecated. Everyone will just not use WSDL/SOAP when there is the REST/POX binding and they'll slow boil it to death.
The spec is really young, but looks promising. They had the word "pub/sub" in there so I'm happy. Not included in this version of the spec though. Perhaps I'll have to try to contribute.
Probably a couple years before it starts becoming mainstream, but color me hopeful. Wow, maybe I'll have to stop being so full of panic now. I doubt that will happen.
Update (after Easter naivete wore off): Marc Fleury at Jboss no likey SCA. If JBI didn't suck, IMHO, he'd have a better argument. But it does - Java specific SOA doesn't really get you far - at least in my world. Jeez, how did I miss this whole thing last Winter? I was tuned out, but not that tuned out.
Dangit, I probably am going to end up recommending the same thing .. really sad.
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