Invoking an adapter service

Invoking an adapter service occurs when a service requester passes a request message to the appropriate stub program in CICS® Service Flow Runtime using one of the supported interfaces.

The request message is comprised of one or more message headers and application data. It contains the parameters and information necessary to initiate runtime processing and to invoke an adapter service that is deployed in the runtime environment. The message headers vary depending on the interface that is used by the service requester, the deployment pattern of the adapter service, and the types of server adapter that comprise the service.

The service requester can use different interfaces to invoke an adapter service, but can only invoke one adapter service in a unit of work. All of the interfaces support passing the request message in a CICS communication area (COMMAREA). However, when you use a Distributed Programming Link (DPL), you can choose to pass the request message to the appropriate stub program in a CICS COMMAREA or using a channel and containers. If you use a COMMAREA, the maximum length of the entire request message with all the headers is 33,272 bytes. If you use containers, you can send a simplified message header separately from the application data.

If you want to use a channel and containers to invoke an adapter service, apply APAR PK32131 to enable support for this function.