@Override
    public void add(final Path sourceDir) {
        if (forwardQueueConfig.isQueueAndRetryEnabled()) {
            addWithQueueAndRetry(sourceDir);
        } else {
            addDirect(sourceDir);
        }
    }
Holds the state relating to retries. Held in binary form.
stroom-proxy/stroom-proxy-app/src/main/java/stroom/proxy/app/handler/RetryingForwardDestination.java