On Thu, 14 Nov 2024 12:42:44 GMT, Jaikiran Pai <j...@openjdk.org> wrote:
> Hello Mark, > > > is it the case that a try-with-resource, and the implicit final declaration > > of s2, will maintain a strongly reachable reference ? > > Rather than having to declare s2 as a final member variable of > > Socket_getInputStream_read, as done with the reader socket s, or using a > > ReachabilityFence to maintain an extant reference. > > The use (or non-use) of `final` doesn't play a role here. The use of > try-with-resources for the `s2` `Socket` instance (the one which was being > cleaned up by the `Cleaner`) is what enforces the strong reachability. The > JLS (linked in the PR description) explains how the try-with-resources is > implemented - specifically, the compiler introduces bytecode to have an > explicit call to `s2.close()` at the end of that try-with-resources block > (this can be checked by running `javap` against these updated classes). The > presence of that `s2.close()` call is what enforces the reachability of `s2`. > > > I terms of "cleanliness" the listener ServerSocket is implicitly released > > I have now updated the PR to use a try-with-resources for the `ServerSocket` > too. The tests continue to pass with these changes. Cheers JP, thanks for that feedback and for ServerSocket suggestion yes, I appreciate and understand the implicit additions which come with try-with-resource and the autoclose. As such, I was just confirming that as s2 is a local variable, this is is sufficient to extend scope of a strongly reachable reference. in any case ... it's all good "big shout out" to @djelinski for some insightful observation during this issue investigation ------------- PR Comment: https://git.openjdk.org/jdk/pull/22093#issuecomment-2476456402
