Concept of generating proxies:
RFC interface basically defines the following:
1. Name of the interface
2. Parameters (Import, Export, Tables and Change)
3. Exceptions of the interface
Note: Individual data elements of ABAP data dictionary type are declared as attributes of the generated JAVA classes.
Mapping between ABAP and JAVA:
Data type mapping:
The elementary ABAP data types are mapped to primitive data types of the JAVA.
Please go through the following data types mapping.
Data elements of an ABAP Dictionary data type are defined as attributes of the JAVA class. The getter and setter methods enable read and write access to individual data elements.
SAP Connector generates an input class that contains all the importing and changing parameters of the RFC function module. In the same way, it also generates an output class that combines all the exporting, changing and table parameters.
For input class, class name comprises function module name following _Input . For output class, class name comprises function module name following _Output .
Table parameters that a RFC function module returns are represented as lists. For each return table, Connector generates a JAVA class. Line type in table comprises the Dictionary data type. Hence it generates a separate JAVA class for the line type.
Generated class, whose name consists of the function module name followed by the string_Fault, contains all the exceptions of the function module.
The exception class consists of the function module name followed by the string_Fault_Exception.
Function module mapping:
The generated function module proxy class contains all the selected function modules, and these are defined as methods of this class. The class name comprises of the name you enter during generation, and the string _PortType.
During the development of Webdynpro application for BAPI access, we will select Import Adaptive RFC model and select the function modules that need to be imported, by selecting the function module and clicking finish. Netweaver Developer Studio will generate the proxies for the selected function module with the naming conventions and mappings as explained above.
This completes concept of generating java proxies for the Remote function module of any SAP System.