class Connection:
    __instance = None
    @staticmethod
    def getInstance():
        """ Static access method. """
        if Connection.__instance == None:
            Connection()
        return Connection.__instance

    def __init__(self):
        """ Virtually private constructor. """
        if Connection.__instance != None:
            raise Exception("This class is a singleton!")
        else:
            from binhoHostAdapter import binhoHostAdapter
            from binhoHostAdapter import binhoUtilities

            utilities = binhoUtilities.binhoUtilities()
            devices = utilities.listAvailableDevices()

            if len(devices) > 0:
                Connection.__instance = binhoHostAdapter.binhoHostAdapter(devices[0])
            else:
                raise RuntimeError('No Binho host adapter found!')