Raise custom exception

Hi experts,

I have synchronous scenario and in response inbound message I have Fault type ft_my_error_message.

My question is: how I can raise my custom exception ft_my_error_message in mapping.

I would like to send some information in my custom exception and catch it in ABAP proxy. With

throw new StreamTransformationException("my message"); 

I’m losing response message and in ABAP proxy I don’t know is my custom error occurred or something else.

Thanks

  Vedran