Re: HashMap get/put
Peter Duniho wrote:
I know what I suspect: since HashMap (and Map) pre-date generics in
Java, the types already have an overload that takes Object as an
argument. Due to the decision to reuse the existing implementations
for the non-reified generics feature in Java, there wasn't any
feasible way to eliminate the possibility of passing an Object (thus the
compile-time assurance I mentioned earlier isn't really a benefit
available in Java), and absent that there just wasn't a strong
argument _against_ allowing Object as an argument.
Not true. The same feature of generics that controls the arguments to put()
could have controlled the argument to get(). A deliberate decision was made
to have get(Object) instead of get(K) [1], and reification has nothing to do
with it.
1. Likewise Set.contains(Object) and Set.containsAll(Collection<?>), but
Set.addAll(Collection<E>). Very consistently, you can add only something of
the proper type, but you can look for things of any type at all.
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