The Honolulu airport Admirals Club is a shared lounge with Japan Airlines. It’s actually controlled by JAL, but is branded both a Japan Airlines Sakura Lounge and an American Airlines Admirals Club.
Airline lounges in Honolulu (and Hawaii generally) are quite weak, so this is hardly one of the inferior lounges at the airport. It’s an air conditioned place to sit, but not worth coming to the airport early for.