A resource adapter is a system-level software driver that a Java application uses to connect to an enterprise information system (EIS).
A resource adapter plugs into an appserver and provides connectivity between the EIS, the application server, and the enterprise application.
An appserver vendor extends its system once to support the connector architecture and is then assured of seamless connectivity to multiple EISs. Likewise, an EIS vendor provides one standard resource adapter with the capability to plug into any application server that supports the connector architecture.
WAS provides the relational resource adapter (RRA) implementation in this release. This resource adapter provides data access through JDBC calls to access the database dynamically. The connection management is based on the JCA connection management architecture. It provides connection pooling, local transaction, and security support.
Container-managed persistence (CMP) beans data access is managed by the WebSphere Persistence Manager indirectly. The JCA Specification supports Persistence Manager delegation of the data access to the JCA resource adapter without knowing the specific backend store. For the relational database access, Persistence Manager utilizes the relational resource adapter to access the data from the database. You can find the supported database platforms for the JDBC API at the WAS prerequisite Web site.