it would be nice to set a custom error code maybe
combined with an error message in case an action
couldn't be processed right. A method like
action.setUPnPError(int code, String message)
would be nice. The set of Error Code and Error Message
could be checked if the implementation of the
ActionListener returns a "false". In case it is set, the
reply could be changed according to the error message.
What do you think?