The J2EE Connector Architecture (JCA) defines a standard architecture for connecting the J2EE platform to heterogeneous Enterprise Information Systems (EIS) including transaction processing systems such as CICS(R) Transaction Server and Enterprise Resource Planning systems such as SAP. For the complete JCA specification, visit http://java.sun.com/j2ee/connector/download.html.
The connector architecture enables an EIS vendor to provide a standard resource adapter for its EIS. A resource adapter is a middle-tier between a Java(TM) application and the EIS that enables the Java application to connect to the EIS. The Java applications include applets, servlets, and enterprise beans. A resource adapter plugs into any application server supporting the J2EE Connector Architecture so that any application running on that server can access the EIS. Similarly, an application server vendor only needs to extend its system once to support the J2EE Connector Architecture. The vendor then supports connectivity to multiple EISs.
A resource adapter developer provides a set of Java interfaces and classes as part of the resource adapter implementation. The Java interfaces and classes are packaged together with a deployment descriptor (ra.xml) to create a Resource Adapter Archive (RAR) file. This file deploys the resource adapter into an application server.
The J2EE Connector Architecture defines the following components: