protected void appendInterfaces(final Class<?>[] interfaces) {
        if(null != interfaces && interfaces.length > 0) {
            if(null == this.interfaces) {
                this.interfaces = new ArrayList<Class<?>>();
            }

            for(Class clazz : interfaces) {
                if(!this.interfaces.contains(clazz)) {
                    this.interfaces.add(clazz);
                }
            }
        }
    }