RabbitMQ/Spring migration - Step 1: Less boilerplate

RabbitConfig.java

@PostConstruct
public void createExchangesAndQueuesAndBindings() {
    // only one line left for each exchange/queues association!
    createAndBindQueuesToFanoutExchangeAndDeadLetter(EMAIL_UPDATED_EXCHANGE, MAILCHIMP_EMAIL_UPDATED_QUEUE);
    // ... other associations...
}

private void createAndBindQueuesToFanoutExchangeAndDeadLetter(String exchangeName, String... queueNames) {
    FanoutExchange exchangeBean = createExchangeBean(exchangeName);

    for (String queueName : queueNames) {
        Queue queue = queueWithDelayedRetry(queueName);
        Binding bindingToExchange = BindingBuilder.bind(queue).to(exchangeBean);
        Binding bindingToDeadLetter = BindingBuilder.bind(queue).to(backFromTheDeadExchange()).with(queueName);

        String beanPrefix = queueName.replace(".", "").replace("queue", "");
        beanRegistry.registerSingleton(beanPrefix + "Queue", queue);
        beanRegistry.registerSingleton(beanPrefix + "ExchangeBinding", bindingToExchange);
        beanRegistry.registerSingleton(beanPrefix + "DeadLetterBinding", bindingToDeadLetter);
    }
}

private FanoutExchange createExchangeBean(String exchangeName) {
    FanoutExchange bean = new FanoutExchange(exchangeName);
    String beanPrefix = exchangeName.replace(".", "").replace("exchange", "");
    beanRegistry.registerSingleton(beanPrefix + "Exchange", bean);
    return bean;
}