Implementing the Proxy Source Code 
Procedure
The provider proxy comprises an ABAP proxy interface and an implementing class that uses the proxy interface. The implementing class contains the operations designed in the Enterprise Services Repository in the form of methods. To implement the functionality of a service operation, the methods need to be filled with application code.
In the Enterprise Services Browser (transaction code SPROXY), perform the following steps:
Locate the generated provider proxy and go to the Properties tab.
Double-click the provider class.
The methods that correspond to the operation are displayed in the Class Builder.
Double-click the method that you want to implement.
Add the code – the implementation of the proxy method.
Next, you need to configure the service interface.