Prior to JCA, vendors had to support a variety of custom adapters for integrating their EIS. These adapters provided custom native interfaces, which were complex to incorporate and limited to only one EIS. This meant that application programmers had to deal with as many adapters as the number of EIS their application communicated with.

The significant limitations were:

• Application programming for the EIS was proprietary; there was no generic platform for integration with the open architectures.
• Custom adapters lacked support for Connection Management, this meant that connection pooling had to be implemented in code.
• There was no standard infrastructure solution available to provide a vendor-neutral security mechanism and generic transaction mechanism support to multiple EIS resource managers.

J2EE Web Application Isolation

The J2EE specification mandates that J2EE-compliant application servers partition web applications by assigning them different class loaders. As a result, two web applications cannot directly share resources even though they are in the same JVM instance and share the same process space. This ability to have multiple applications running independently in the same process space makes the Java platform well suited for developing scalable applications.

Operational Challenge

JCA: J2EE is used to ease the development and maintenance of enterprise-scale web applications. For this class of application, connecting to one or more external systems is the rule rather than the exception. At the current time, organizational enterprise must either use JDBC: Java Database Connectivity for data-level access or buy, build, or partner to obtain richer application-level connections. Current adapters are platform-specific and offer varying subsets of application functionality. Each adapter requires the developer to learn a new programming interface. It is not uncommon for adapters to suffer from poor scalability and performance. Complex or poorly documented application APIs are common causes of an inferior interface. JCA defines a set of service contracts that a connector developer can expect will be available to the adapter at application runtime: connection management, transaction management, and security.

Qualifying a Training Assignment

The Java platform and language can be used to solve common architectural problems by using connection adapters. JCA are created and published to expose proprietary, legacy services in a standardized manner to potential consumers. The services expected and the clients expected communication setup will be clients through the Service End Points. In conjunction with qualifying a JCA training assignment, SYS-ED will review the integration of connection pooling, security identity propagation and transaction control used at the client organization. This information will then be incorporated into the lesson plan.

Client-specific Tailored Exercises

There are new electronic medical record guidelines mandated by the federal government, a patient’s record must be made available to numerous systems throughout the country. The JCA can be used for connecting to a UNIX box supplying the medical records and test information. A JCA connector will be developed and deployed. It will be used to access an Enterprise Information Systems on a UNIX-variant, Microsoft Windows or IBM mainframe platform.

SOA: Service Oriented Architecture Courses