STAR and PLUS networks using credit union ATM card in China

I have an ATM card with my credit union in the USA that uses a 4-digit PIN and connects with the STAR and PLUS networks. Wil I be able to use this card at the ATMs at the Bank of China in China? I also have a US Visa card that is not connected to a bank account, only to a cash advance. How does that work in China?