On 16/04/2012 14:49, Salter, Thomas A wrote:
:
I also wonder why it's even an option to specify an explicit address
family. According to the Java Docs this is the only place in the
entire JDK that doesn't just infer the family from an address.
There's no other references to ProtocolFamily and StandardProtocolFamily.
On Windows issue then which version of Windows do you see this?
On the ProtocolFamily then this is part of the multicast support that
was added in JDK7. Here's how it's worded in MulticastChannel:
"The creation of the channel should specify the |ProtocolFamily|
<http://docs.oracle.com/javase/7/docs/api/java/net/ProtocolFamily.html>
that corresponds to the address type of the multicast groups that the
channel will join. There is no guarantee that a channel to a socket in
one protocol family can join and receive multicast datagrams when the
address of the multicast group corresponds to another protocol family.
For example, it is implementation specific if a channel to an |IPv6|
<http://docs.oracle.com/javase/7/docs/api/java/net/StandardProtocolFamily.html#INET6>
socket can join an |IPv4|
<http://docs.oracle.com/javase/7/docs/api/java/net/StandardProtocolFamily.html#INET>
multicast group and receive multicast datagrams sent to the group."
In time then one could envisage being able to create classic
DatagramSocket or MulticastSocket instances to an IPv4 only or IPv6 only
socket.
-Alan
