8231259: (dc) DatagramChannel::disconnect re-binds socket to the wildcard address (macOS)

[Chris Hegarty]

> On 19 Nov 2019, at 12:42, Alan Bateman <Alan.Bateman at oracle.com> wrote:
> 
> On 19/11/2019 11:58, Chris Hegarty wrote:
>> :
>> For example, if the “repairing” fails to re-bind to the original port then an exception will be thrown from repairSocket. Subsequently, the finally block will attempt to retrieve the local address ( which I guess will also fail with an exception ( Ugh! this will suppress the re-binding exception ) ).
> Not quite, Net.localAddress will return the wildcard address and port 0 to indicate unbound. We could potentially map that to null but I don't think we want to encourage anyone to attempt to re-bind when disconnect fails. I think we stick with the recommendation in the javadoc to close the channel when disconnect fails.

FTR  I agree with the existing recommendation: to close the channel when disconnect fails. - I am not arguing to change this.

What I take issue with, since these changes greatly expand the scope of potential for failure in disconnect, is the qualification in the apiNote that contains the recommendation. The qualification limits the unspecified behaviour to the channel’s socket. I think this qualification should be removed.

-Chris.