On Mon, 26 Oct 2020 17:13:05 GMT, Rémi Forax
<[email protected]> wrote:
>> We can clarify the new methods and tie them closer to method handle
>> semantics. I suggest the names `asExactInvoker` and `asInvoker`, referencing
>> `MethodHandles.exactInvoker` and `MethodHandles.invoker` respectively. (The
>> term "generic" is really reserved for erased method types, and otherwise
>> used internally as the generic invoker.)
>>
>> The `VarHandle` documentation already specifies that:
>>
>> * <p>
>> * Invocation of an access mode method behaves as if an invocation of
>> * {@link MethodHandle#invoke}, where the receiving method handle accepts the
>> * VarHandle instance as the leading argument. More specifically, the
>> * following, where {@code {access-mode}} corresponds to the access mode
>> method
>> * name:
>> * <pre> {@code
>> * VarHandle vh = ..
>> * R r = (R) vh.{access-mode}(p1, p2, ..., pN);
>> * }</pre>
>> * behaves as if:
>> * <pre> {@code
>> * VarHandle vh = ..
>> * VarHandle.AccessMode am =
>> VarHandle.AccessMode.valueFromMethodName("{access-mode}");
>> * MethodHandle mh = MethodHandles.varHandleExactInvoker(
>> * am,
>> * vh.accessModeType(am));
>> *
>> * R r = (R) mh.invoke(vh, p1, p2, ..., pN)
>> * }</pre>
>> * (modulo access mode methods do not declare throwing of {@code Throwable}).
>> ...
>>
>> We will need to adjust this section, i can help, but first let us reach
>> agreement on this approach.
>
> Paul,
> an invoker has the MethodHandle (resp. VarHandle) as first argument so it's
> not the same semantics.
I've updated the implementation of accessModeType to work with the ordinal
directly. Note that it was using the AccessType ordinal though, so I also had
to change the parameter type of accessModeTypeUncached, and the respective
implementations, to use AccessType directly (luckily this was possible, since
the current implementations all just used the AccessType).
-------------
PR: https://git.openjdk.java.net/jdk/pull/843
