On Mon, 13 Sep 2021 11:06:15 GMT, Сергей Цыпанов
<github.com+10835776+stsypa...@openjdk.org> wrote:
> Currently the method is implemented like
>
> public List<Class<?>> parameterList() {
> return Collections.unmodifiableList(Arrays.asList(ptypes.clone()));
> }
>
> This seems to be excessive, as three objects are allocated here. Instead we
> can use `List.of(ptypes)` which doesn't allocate anything for empty array and
> for one of length 1 and 2 it allocates lightweight objects with 2 fields,
> still copying longer arrays. This is likely to be fruitful as most of methods
> have 0-2 parameters.
>
> Also there is a couple of cases when `MethodType.parameterLis()` is called to
> get its size, which is excessive either as we can use
> `MethodType.parameterCount()` instead.
This pull request has now been integrated.
Changeset: 4c673df3
Author: Sergey Tsypanov <sergei.tsypa...@yandex.ru>
Committer: Jorn Vernee <jver...@openjdk.org>
URL:
https://git.openjdk.java.net/jdk/commit/4c673df31e46644b21fefa51e0ea01f7d9b94856
Stats: 7 lines in 2 files changed: 0 ins; 0 del; 7 mod
8273656: Improve java.lang.invoke.MethodType.parameterList() and its usage
Reviewed-by: jvernee, vlivanov, mchung
-------------
PR: https://git.openjdk.java.net/jdk/pull/5489
