How to use REST as Datasource for JasperReports Server 6.0.1

HI I am new to jasper reporting, I want to consume REST services to get data from existing system to display using JasperReports Server.
 

So the idea is my existing system will invoke perticular report which will call perticular report in the JasperReports Server, depending on which report is called JSS have to invoke that report and report will query data from perticualr REST webservices and then render that data in specified formate.

Please help me in this !!!! Thanks in advance ................................................!!! :)