@Override
    @Deprecated
    public String getPropertyAsString(IClientConfigKey key, String defaultValue) {
        return Optional.ofNullable(getProperty(key)).map(Object::toString).orElse(defaultValue);
    }
Store the default value for key while giving precedence to default values in the property resolver
ribbon-core/src/main/java/com/netflix/client/config/ReloadableClientConfig.java