make LocalChannel part of the SocketChannel hierarchy?

[Iain McGinniss]

In my tests and code, I am often dealing with the SocketChannel  
related interfaces rather than concrete types, and it makes it easier  
for me to use mock objects (either hand written, or produced by  
jMock). As I writer higher and higher level tests, the burden of  
mocking increases, to the point where I'd actually really like  
something that behaves like a real channel in every sense, but does  
not necessarily use external resources that are difficult or time  
consuming to clean up between test runs. LocalChannels would fit this  
requirement nicely, but unfortunately they are not part of the class  
hierarchy for the SocketChannel related types, despite the fact that  
the LocalAddress objects that are used for addressing extend  
SocketAddress.

I think it would be quite trivial to make all the classes in question  
useable in my test cases, by doing the following:

1. Make LocalChannel extend SocketChannel
2. Make LocalServerChannel extend ServerSocketChannel
3. Make LocalServerChannelFactory extend ServerSocketChannelFactory
4. Make LocalClientChannelFactory extend ClientSocketChannelFactory

With these four changes, I believe the rest just falls into place, as  
the LocalAddresses used are already subclasses of SocketChannel and so  
the interfaces are compatible. This would then make it very easy for  
me to test client-server interaction with worrying about available  
ports on the test machine, and make setup / teardown very easy and fast.

I can provide a patch for this, if others agree that this is a  
desirable change?
Iain