Here are some takeaways from Greg Pavlik’s and Clemens Utschig’s outstanding and inspiring presentation yesterday at Oracle Open World on key architectural aspects of Oracle SOA Suite 11.
Clemens and Greg spoke about many aspects from which I share some talking points on Service Component Architecture – SCA.
SCA is still in the standardization process, probably it will take until 2010 to be a final OASIS Standard. Greg made the analogy that SCA is to integration what J2EE was to Java programming. The key umbrella artifact in SCA, the “Composite” is analogous to an EAR in J2EE.
WSDL is a push based service interface and the SCA standard currently is built around classic WSDL based services; Thus, SCA has no publish subscribe (pub sub) functionality. Oracle realized this as a limitation. Thus, to broaden usage of SCA Oracle introduces events into SCA as another endpoint paradigm to the “Event Delivery Network” (EDN). I think this is a smart move – a lightweight means to communicate from applications with BPEL processes is requirement I often ran into at projects. To make sure events are part of the standard asap, Oracle works with the standard committee on “SCA Eventing”. Of course, customers can leave it out when they want to stick to the standard while it is evolving.
SCA Eventing and loose coupling
Designed the right way, SCA events can further enable decoupling/loose coupling when compared to WSDL based endpoints because events free from the need for explicit wiring between services: You just exchange lightweight events with a minimum of technical communication overhead. For example, a WSDL based service can have multiple WSDL parts, while events are limited to just one part.
SCA beyond “SOA Suite classic”
Clemens showed Java Spring exposed in a SCA composite and now Oracle looks to create SCA layers for the integration platform Tuxedo and for C based logic!
I think this is great because more and more SCA becomes the core logic exposure, easily exposing Tuxedo or C based pieces of logic as “first class citizens in SCA world” – and, if carefully exposed through well designed service interfaces – in a SOA world.
Clemens showed all concepts live, so you could feel the need in the room to open JDeveoloper and play with 11g.