Kinda. They do have fun stuff like a cruiser that has a flat deck and carries aircraft, not an aircraft carrier (!!!), a cruiser. And they have been rearming the last two years as it becomes clear their neighbors might need a stick, or at least the threat of one.
They have a navy but it operates as an arm of the US Military, more or less. There are 23 US Military Bases in Japan with 53,973 troops or about a third of the USA's deployed troops worldwide.