On Mon, 12 Jun 2023 19:27:28 GMT, Deepa Kumari <[email protected]> wrote:
>>> Well, in that area we always had deviations on AIX, so definitely this >>> rings a bell. However, since AIX was not the most important platform for us >>> and that particular IPv6/IPv4 multicast feature didn't seem to be mission >>> critical and wouldn't fail TCK tests, we rather resorted to excluding some >>> tests internally, I believe. But it would be good to really resolve this >>> compatibility/spec/documentation issue, if possible. >> >> Thanks. So yes, if some/all of the tests for multicasting were excluded then >> it helps explain why it didn't come up. The spec doesn't require that a >> DatgaramSocket or DatagramChannel to an IPv6 socket be capable of joining an >> IPv4 multicast group. So the tests in several areas might need updates as I >> don't think we've had a platform to date where it wasn't possible. > >> > Well, in that area we always had deviations on AIX, so definitely this >> > rings a bell. However, since AIX was not the most important platform for >> > us and that particular IPv6/IPv4 multicast feature didn't seem to be >> > mission critical and wouldn't fail TCK tests, we rather resorted to >> > excluding some tests internally, I believe. But it would be good to really >> > resolve this compatibility/spec/documentation issue, if possible. >> >> Thanks. So yes, if some/all of the tests for multicasting were excluded then >> it helps explain why it didn't come up. The spec doesn't require that a >> DatgaramSocket or DatagramChannel to an IPv6 socket be capable of joining an >> IPv4 multicast group. So the tests in several areas might need updates as I >> don't think we've had a platform to date where it wasn't possible. > > @AlanBateman , is it possible if there is a central place where the change > could me made for fixing all of the multicast test cases? > IIUC what @deepa181 is saying, it looks like the "IPv4 socket being unable to > join an IPv4 multicast group" problems surfaced when we moved away from > PlainDatagramSocketImpl in JDK 17? Probably because the delegate created does > not factor in the ProtocolFamily and though we started with attempting to > have an "IPv4 multicast socket join an IPv4 group", we end up trying to have > an "IPv4/IPv6 dual-stack socket (the delegate) join an IPv4 group" which AIX > doesn't permit. IIRC It has never been possible to create a non-dual `MulticastSocket` / `DatagramSocket` without setting the property `-Djava.net.preferIPv4Stack=true`. The possibility to select a protocol family independently of this property is only available with `DatagramChannel`. ------------- PR Comment: https://git.openjdk.org/jdk/pull/14142#issuecomment-1601038453
