JCA Adapters:
Are used from within Java EE 5 applications (EJB 3.0) to get connectivity with the external systems.
Have no dependency on the Java CAPS Repository.
Allow EJB applications (equivalent to Java Collaboration Definitions) to use the adapter's fine-grained API calls inside business logic
Are globally deployed and shared among more than one Java EE application.
Can share a common pool with a fixed set of properties.
Can easily have configuration properties changed after the project has been built and deployed.
Use the same code base as eWays.
eWay Adapters:
Are used in Java CAPS Repository-based projects to get connectivity with the external systems.
Are usually dependent on OTDs that provide fine-grained API for use in Java Collaboration Definitions where business logic is implemented.
Are embedded within the .EAR file; the scope of each eWay at runtime is limited to that EAR only.