BEA WebLogic Server, User Manual

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Sample Wrapper Module to Call Functions on Remote Destinations (Service)
D-10 BEA Systems, Inc.
Sample Wrapper Module to Call Functions on Remote Destinations
(Service)
This topic describes how to invoke a service that employs SAP remote data. For example,
you can use this technique to write a function using C on a UNIX server that queries an
Informix database and returns the response to SAP.
The ABAP command, CALL FUNCTION, takes as an argument, DESTINATION. Using RFC
(Remote Function Call) destinations, programs can be executed on external systems, and
the results can be returned into SAP function module programs. For more information on
this functionality, see your SAP documentation, which is available at the following URL:
http://help.sap.com
Since DESTINATION is not part of an individual BAPI (Business Application Programming
Interface) or Remote Function Module (RFM), but a parameter of the SAP function
mechanism, you require a
wrapper module to invoke it as a service. In addition, you must
invoke the wrapper module in place of the original function.
The wrapper module is written using SAP’s ABAP/4 programming language and contains
the same input and output parameters as the original function. You can obtain all of the
parameters of a remote function in the function editor by selecting Edit and then, Pattern
and entering the function name.
The destination inside the wrapper module must be a valid SAP RFC destination with an
RFC Server program running on the remote host. For more information, see SAP’s RFC
Programming manual, which is available at the following URL:
http://service.sap.com
The RFC Server program must return the data to SAP in a format that follows the exact
structure of the Remote Function interface, or an abnormal ending occurs in SAP.