https://www.youtube.com/watch?v=sYtxtH_KGU4

https://www.youtube.com/watch?v=wvo-KYyEOX4

Please watch these videos it will be helpful for u.In this videos steps to a build a jasper report using ireports in openerp.

Refer below link may help you

http://pinakinnayi.blogspot.in/2012/05/jasper-report-in-openerp.html

http://stackoverflow.com/questions/14254050/jasper-report-module-for-openerp-7

https://www.odoo.com/forum/help-1/question/how-to-use-jasper-report-server-with-openerp-4714

https://www.odoo.com/forum/help-1/question/jasper-report-module-for-openerp-7-10499

http://www.zbeanztech.com/blog/jasper-reports-openerp-basics?page=1