WebLogic 10.3 Tech preview now supports Service Component Architecture (SCA) runtime. The SCA specification has two main parts: implementation of service components (which can be done in any language) and the assembly model which is the linking of components through wiring (which is done through XML files). Every component technology (Spring, POJO, EJB etc) that wants to participate in the SCA framework should support SCA metadata. The SCA specification defines language bindings for each of the technologies.

The claim to fame for SOAP based web services is that it provided a programming model where clients do not care as to which programming language the service is implemented. The client can be written in any language that has a SOAP binding. The only restriction on the client is that it has to use the SOAP API. Thus by service enabling your existing business services and modifying your legacy clients to speak SOAP, web services have made enterprise integration easier compared to yester years.

Now SCA takes this interoperability to the next level, where now your clients can stay as is and do not have to use the same transport as the service. All the client knows is that it is a remotable service.

Let us say you have a Java client that was talking to an EJB. Now this EJB has been converted into a web service. In this case, the Java client does not have to change to use SOAP API. Instead it can still use its EJB client code because the web service (which is an SCA component) can be decorated with an EJB binding. Thus the service can be implemented in one technology such as Spring, POJO, EJB, web service or BPEL and it can be decorated with a different binding (Spring, POJO, EJB, web services etc) to support different clients. By including the SCA runtime on WLS, customers can take advantage of the RASP functionality provided by WLS for the deployed SCA components. The infrastructural capabilities such as security, transactions, reliable messaging that are to be handled declaratively through policies under the SCA specification can all be provided by WLS.

Read the complete post by Vijay Mandava of BEA Systems.