With z/TPF support for Java™, you can extend traditional z/TPF applications using the Java programming language, write new business logic in Java and use open source Java packages on your z/TPF system. The z/TPF rules engine driver for Java demonstrates how you can use Java to add rules engine processing to an existing z/TPF application and how a rules engine can simplify and add a layer of abstraction to sometimes fragile, messy business logic.
The z/TPF rules engine driver for Java has two core components, the flightrules Application Manager for Java (JAM) and the flight pricing driver (QRUL). The flightrules JAM is the Java component of the driver and contains the priceFlight REST service. The priceFlight REST service is written in Java and uses an open source Java rules engine that calculates the price of a flight based on various business rules (seat availability, loyalty status, etc.). The priceFlight REST service is packaged and deployed as part of the flightrules JAM on your z/TPF system.
The flight pricing driver (QRUL) represents a traditional z/TPF application written in C/C++ and calls the priceFlight service using the tpf_srvcInvoke() API. To call the priceFlight service, the QRUL driver creates a typical C/C++ structure to hold the input for the priceFlight service, passes the structure as a parameter on the tpf_srvcInvoke() API, and on return from the tpf_srvcInvoke() API, receives a separate C/C++ response structure with the results of the priceFlight service.
Taken together, these components provide a working example that shows how you can use Java on your z/TPF system and take advantage of Java by calling it from your z/TPF applications.
More information for this driver and the driver download package are available on the z/TPF rules engine driver for Java download page.