RFR: 8282662: Use List.of() factory method to reduce memory consumption [v3]

[Weijun Wang]

On Thu, 10 Mar 2022 08:52:17 GMT, Сергей Цыпанов <duke at openjdk.java.net> wrote:

>> `List.of()` along with `Set.of()` create unmodifiable `List/Set` but with smaller footprint comparing to `Arrays.asList()` / `new HashSet()` when called with vararg of size 0, 1, 2.
>> 
>> In general replacement of `Arrays.asList()` with `List.of()` is dubious as the latter is null-hostile, however in some cases we are sure that arguments are non-null. Into this PR I've included the following cases (in addition to those where the argument is proved to be non-null at compile-time):
>> - `MethodHandles.longestParameterList()` never returns null
>> - parameter types are never null
>> - interfaces used for proxy construction and returned from `Class.getInterfaces()` are never null
>> - exceptions types of method signature are never null
>
> Сергей Цыпанов has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8282662: Revert dubious changes in MethodType

src/java.base/share/classes/sun/security/validator/EndEntityChecker.java line 119:

> 117:     // TLS key exchange algorithms requiring keyEncipherment key usage
> 118:     private static final Collection<String> KU_SERVER_ENCRYPTION =
> 119:         Arrays.asList("RSA");

I understand that you haven't modified the `KU_SERVER_KEY_AGREEMENT` on line 122 because it has 4 elements. However, these 2 nearby lines using different styles look a little strange to me. Why restrict the number to 0, 1, and 2? If we have defined methods with up to 9 arguments, does that mean the new type is suitable for 9 elements?

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PR: https://git.openjdk.java.net/jdk/pull/7729