RFC Server module components

The RFC Server module is a connector module written in Java that supports RFC calls directly from an SAP application. It extends the Vision Connector Framework by implementing the VisionConnectorAgent class. The RFC Server module uses the SAP RFC libraries that are written in Java and C, which enables external programs to communicate with an SAP application.

Figure 27 illustrates the overall architecture of the RFC Server module. The RFC Server module is made up of the connector framework, the connector's application-specific component for RFC Server, RFC Server-specific business object handlers, listener threads, and the SAP RFC Library.

Figure 27. RFC Server module Architecture

The RFC Server module components:

Listener Threads

Listener threads handle all of the RFC calls between the RFC Server module and the SAP application. When the connector starts up, the init() method creates a main thread that spawns a configurable number of listener threads. Each listener thread opens a handle to the SAP Gateway.

The listener threads:

Note:
A thread listens continuously in a synchronous manner for events from RFC-enabled functions that it supports.

RFC Server-specific business object handlers

The RFC Server-specific business object handlers are unique to each RFC-enabled function in the SAP application. Each business object handler is instantiated by a listener thread and invokes an associated business object.

Because the RFC Server module acts as a server to the SAP application, it "pushes" or sends events from the SAP application to the integration broker. This behavior is very different from other modules, which poll the application for events. Because of this difference, RFC Server-specific business object handlers perform different tasks from other business object handlers.

Once instantiated, the RFC Server-specific business object handler:

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