DatagramSocket vs DatagramChannel behavior in disconnect()

[Florian Weimer]

Sockets preserve the local address on disconnect(), but channels don't. 
  Bug 6431343 reflects that, but this is still surprising and violates 
the NetworkChannel contract ("Once an association is established then 
the socket remains bound until the channel is closed").

I see this on Linux.  Behavior on other systems is different.  For 
datagram sockets, the native disconnect() implementation has a 
Linux-specific workaround for this, but DatagramChannel lacks it.

What's the best way to address this?  Adjust the NetworkChannel 
documentation?  Apply the DatagramSocket workaround to DatagramChannel 
as well?

-- 
Florian Weimer / Red Hat Product Security Team