It is possible to create and implement a JCA adapter. The resource adapter represents a set of classes used by a J2EE application server to connect to a specified enterprise system. As previously mentioned, the JCA adapter’s functionality is similar to a JDBC driver and how it connects to repositories.
For further information on how to create and implement a resource adapter, refer to the JCA specification, which can be downloaded from Sun’s web site. Another valuable resource is J2EE Connector Architecture and Enterprise Application Integration by Rahul Sharma, Beth Stearns, and Tony Ng (Addison-Wesley, 2001). It covers all aspects of the JCA in depth, including detailed information on how to implement a JCA adapter. JCA is an invaluable addition to the J2EE set of specifications.