public static String extractPropertyKey(String key) {
        if (StringUtils.isBlank(key)) {
            return "";
        }
        return key.substring(key.lastIndexOf(KEY_SEPARATOR) + 1);
    }
The last field of key is actual property key
core/api/src/main/java/com/alipay/sofa/rpc/dynamic/DynamicConfigKeyHelper.java