On Thu, 16 Feb 2023 04:39:20 GMT, Stuart Marks <[email protected]> wrote:
>> I've written a CSR report for this PR as below. Could someone please help
>> me to submit it to the JBS if it looks okay? Thank you!
>>
>> ---
>>
>> **Compatibility Risk:** minimum
>>
>> **Compatibility Risk Description:** No implementation is modified
>>
>> ## Summary
>>
>> Document the current behavior of `java.util.Arrays.asList(Object...)` that
>> it will throw an `ArrayStoreException` when an element of wrong type is
>> trying to be set into the list.
>>
>> ## Problem
>>
>> `java.util.Arrays.asList(Object...)` is a widely used method that wraps an
>> object array into a mutable `List`. The specification of methods
>> `List.set` and `ListIterator.set` indicates that implementations should
>> throw a `ClassCastException` when the class of the specified element
>> prevents it from being added to this list. However when an application tries
>> to store an element that is not compatible with the backing array component
>> type via the returned list, an `ArrayStoreException` will be thrown instead
>> of `ClassCastException`, which violates the `List` specification.
>>
>> ## Solution
>>
>> Since this method is widely used, we do not change the current behavior.
>> Instead, we document the current behavior of
>> `java.util.Arrays.asList(Object...)` that it will throw an
>> `ArrayStoreException` when an element of wrong type is trying to be set into
>> the list.
>>
>> ## Specification
>>
>> Add the following `@apiNote` section into the `java.util.Arrays.asList`
>> specification:
>>
>>
>> * @apiNote
>> * The {@link List} returned by this method does not conform to the
>> * specification for {@link List#set} and {@link ListIterator#set}.
>> * It is possible for the type parameter {@code T} of the returned list
>> * to differ from the array's component type. This can occur, for
>> example,
>> * if the array argument type has been upcast from its component type:
>> *
>> * {@snippet :
>> * String[] strings = new String[1];
>> * List<Object> objects = Arrays.asList((Object[])strings);
>> * }
>> *
>> * Writing an element into the returned list may result in an
>> * {@link ArrayStoreException} instead of {@link ClassCastException}
>> being
>> * thrown if the element is incompatible with the underlying array's
>> * component type:
>> *
>> * {@snippet :
>> * objects.set(0, Integer.valueOf(0)); // throws ArrayStoreException
>> * }
>
> @yuantj
>
> The proposed change needs additional editing. In particular, the issue is not
> about conformance. I'd need to suggest changes that you'd apply, in order to
> get the text in the change to match what I'm essentially writing myself. In
> addition, CSR also needs quite a bit of editing, which I'd write myself
> anyway. Thus I don't think it's worth continuing with this PR. Thanks for
> your efforts, though, in raising the issue and attempting to address it.
>
> The main point is that this isn't a spec violation, and if it were, one part
> of the specification can't "note" itself out of conforming to another part of
> the specification. The issue is really a clarification that some
> implementations might throw exceptions beyond those explicitly listed in the
> interface.
@stuart-marks Okay, I got it. Thanks for your reviewing anyway. Going to close
this PR.
-------------
PR: https://git.openjdk.org/jdk/pull/12135
