Hotel address needed?

Hello, I am Austrian and I want to travel to Shanghai for one week with my boyfriend end of August. As He will already be there before me he wanted to book our hotel spontaneously. But for my Visa I need an address. Is it possible to get the Visa without knowing the address from the hotel?

Or in another case that we already book the hotel but then really don't like it and want to change or there are some other problems. Will there be a problem with the Visa if I change Hotel?

Thanks for your help.