Do some research on the Dept of Immigration and Border Protection website. If you are on a student visa and want to apply for PR, you may try and do so via the General Skilled Migration Program.
http://www.immi.gov.au/students/students/extending_your_stay

Just about everyone gets PR after an Australian degree. Many use it to immigrate.

Firstly – Immigration generally changes the rules and requirements almost every year. So the requirements for applying for residency now may not be the same after you graduate.
Secondly – depends on how good you are convincing the relative authorities that you are a “genuine” student. I wont go into detail but basically there are a few pre-screening processes as well as monitoring details that can ensure both immigration, and the university that you are in fact here in Australia for the sole purpose of obtaining an education. Nothing else.