Adaptable World

As you can see, adapters are a huge part of application integration. They remove us from the need to deal with the interface details that communicate with a variety of different source and target systems. What's more, adapters provide more consistency from interface to interface because they are, by design, reusable from problem domain to problem domain. However, adapters do not remove the need to have a complete integration solution, including transformation, routing, and process integration. They merely deal with the connectivity to the source or target systems.

Adapters are becoming more important as we look to leverage new standards such as Web services. They need to change from information oriented to service oriented, something that will not happen overnight. There are very different problems to solve as well. What's more, many applications just won't provide service-level access to their internal functions, serving up simple data instead. This is not the fault of the adapter developer, but a limitation of the application interface. As time goes on, a greater number of simple information interfaces will become service based, perhaps even leveraging service-oriented access standards such as WSDL and SOAP.

Emerging standards such as JCA hold the promise of making adapters reusable across applications as well as across vendors. It's going to be some time, however, before we have a critical mass of JCA adapters and all are working and playing well together. In addition, the standard is likely to morph, hopefully to an improved state, accounting for needs such as metadata and scalable communication. Looking forward, it's clear that JCA will include these capabilities in the long term. In the short term, most problem domains will leverage a mix-and-match approach, using both standard and proprietary adapters.