Australian Living in Shanghai wanting to Apply Visa in Japan

I'm an Australian been studying/working in Shanghai for a few months now on a M type. It's about to expire in a few weeks and was wondering if it's an option to go to Japan and apply for a student X type for 90 days? Which is more acceptable 30 days or 90 days? Do you have to be either Chinese or Japanese? As many details as possible would be great help. Thanks!