integration

Dear experts

My clients wants to integrate Payroll system into SAP.Client is not having SAP HR module just he need to integrate that Payroll module in FICO.In Java application he had the table Employee master and all the required information of Payroll. and he just wants grand total of Salary details to be displayed in SAP instead of each and every employee information individually.So he is asking me From d SAP screen he wants to see d Java screen which holds all detailed information.Is it possible with XI.From SAP screen how can i extract d data of Java using XI.

Means I need to extract d detailed data from Java using Xi just in SAP only all employees salary total shoul be displayed.Is it possible using XI and Can we see the detailed information of Java from our SAP screen.

How i need to do d above process using XI