RFR: 8283772: Make sun.net.dns.ResolverConfiguration sealed

Tue Mar 29 08:39:50 UTC 2022

On Mon, 28 Mar 2022 21:44:36 GMT, Aleksei Efimov <aefimov at openjdk.org> wrote:

> The following fix seals `sun.net.dns.ResolverConfiguration` abstract class.
> `sun.net.dns.ResolverConfigurationImpl` is the only permitted subclass which has two O/S specific implementations: for `Windows` and `Unix` architectures. Both of them are marked as `final`.
> 
> Testing: `jdk-tier1`, `jdk-tier2`, `jdk-tier3` and `java.naming` JCK tests show no failures with the change.

LGTM.

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PR: https://git.openjdk.java.net/jdk/pull/8006