}
        return null;
    }

    @Override
    public String toString() {
        return DfTypeUtil.toClassTitle(this) + ":{}";
    }

    @Override
    public void adjustActionResponseJustBefore(final ActionRuntime runtime, final ActionResponse response) {
        final String mimeType;
        if (response instanceof HtmlResponse) {
            mimeType = "text/html";