class ExchangeBrokerClient extends Client {

    public Optional<Cdr> getLastMessageFromQueue(final String queueName) {
        return Optional.ofNullable(
            messagesByQueue.getOrDefault(queueName, new LinkedList<>())
                .peekLast()
        );
    }

    public  ExchangeBrokerClient(String clientConfig);
    public  ExchangeBrokerClient(String primaryClientConfig, String secondaryClientConfig);
    public  ExchangeBrokerClient(String primaryClientConfig, String secondaryClientConfig, ProtocolConfig protocol);

}