Java: getClass() of bounded type

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If getClass() returns Class<? extends X>, nothing really bad can happen; actually it’ll help a lot of use cases.

The only problem is, it is not theoretically correct. if an object is an ArrayList<String>, its class cannot be Class<ArrayList<String>> – there is no such class, there is only a Class<ArrayList>.

This is actually not related to erasure. If one day Java gets full reified types, getClass() should still return Class<? extends |X|>; however there should be a new method, like getType() which can return a more detailed Type<? extends X>. (though, getType may conflict with a lot of existing classes with their own getType methods)

For the timing being, since Class<? extends X> might be useful in a lot of cases, we can design our own method that does that

static <X> Class<? extends X> myGetClass(X x){ ... }

but it’s understandable they wouldn’t put this kind of hack in standard lib.

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