Hi Tanmoy,
ABAP proxy communication is well supported in Java-only installations (PO and AEX). Please use SOAP adapter, XI message protocol for this.
Few examples can be found in How to Set Up the Communication between ABAP Backend and SOAP Adapter using XI Protocol, Some Prerequisite for SOAP Communication with XI Protocal in SAP system, SOAP with XI 3.0 message protocol.
Regards,
Vadim