/**
     * Prepares the fields.
     */
    protected void setupFieldDescs() {
        if (beanClass.isInterface()) {
            setupFieldDescsByInterface(beanClass);
        } else {
            setupFieldDescsByClass(beanClass);
        }
    }

    /**
     * Prepares the fields defined in the interface.
     *
     * @param interfaceClass
     *            the target interface
     */