On Mon, 13 May 2024 13:41:50 GMT, Jaikiran Pai <j...@openjdk.org> wrote:
>> All random number generator algorithms are implemented in module
>> `java.base`. The usage of `ServiceLoader` in `j.u.r.RandomGeneratorFactory`
>> is no longer needed.
>
> src/java.base/share/classes/java/util/random/RandomGeneratorFactory.java line
> 299:
>
>> 297: private void ensureConstructors() {
>> 298: if (ctor == null) { // volatile load
>> 299: synchronized (rgClass) {
>
> Here too I think we should synchronize on `this` - we would want to allow
> multiple different instances of a `RandomGeneratorFactory` for the same
> `RandomGenerator` class type to be able to concurrently instantiate their
> individual instance fields (like the `ctor`(s) and `properties`).
Then I would even remove the double-checking idiom, the `volatile` on `ctor`
and `properties`, and declare methods `getProperties()` and
`ensureConstructors()` as `synchronized`.
I'm not sure that the double-checking optimization brings much value on
contemporary JVMs.
But I feel that the followup PR discussed before wouldn't need `synchronized`
at all.
WDYT?
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/19212#discussion_r1598520001
