Getting an exchange student visa for China in Japan (I am not Japanese)

I got accepted by a Chinese university but I am currently finishing my studies in one in Japan. I have not time to come back to my country and apply for it there meanwhile so I should apply for the exchange student entry permit in Tokyo.

However, the information is not clear and it seems that only talks about tourist and bussiness types and little information for non Japanese citizens.

What should I do?

Thanks