What if Japan invaded Australia before the bombing of Pearl Harbour? Would of you think that Australia would still hate Japan for the occupation or would it end with a friendly apology?

I don't think there would be any hatred for a couple of reasons. The Japanese didn't have enough troops for a full scale invasion, they didn't have enough troops to occupy Australia, they didn't have the resources yet to have a chance of an invasion. Even if it did somehow happen, there would be no hatred. The Aussies are great people.