Hi Kavuri,
Check this William Li's document (Only for PI 7.1 and older versions) http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/c0487ced-f537-2d10-249d-f6c7323c272e?quicklink=index&…
And his blog for 7.3X versions: Using PI 7.3’s Directory API
I hope these could be helpful in your requirement.
Regards.