protected abstract SelectionKey register (AbstractSelectableChannel ch, int ops, Object att)

Registers the given channel with this selector.

This method is invoked by a channel's register method in order to perform the actual work of registering the channel with this selector.

ch     The channel to be registered
ops     The initial interest set, which must be valid
att     The initial attachment for the resulting key

Returns:  A new key representing the registration of the given channel with this selector