Java doesnt have value types or structs. You have primatives (booleans, integer types and float/double) and then everything else (even the uppercase primative types like Boolean) are reference types, IE on the heap. For stuff that plays with pointers you generally just call into native code, get back a long (the pointer to whatever you just allocated) and you call into native code to do stuff with the pointer. Native code can make a proper java object but it's involved and has all the same cons as allocating one in Java land.

Supposedly records (a pseudo struct) might get stronger optimization options (IE put on the stack) but fundementaly reference types are just pointers and if you get an object via constructor or parameter the language must support you putting it in global state