public class HtmlUnorderedList {
    private List<String> listElements = new ArrayList<>();

    public void addListItem(String listItem) {
        listElements.add("<li>" + listItem + "</li>");
    }

    public String getHtml(String classNames) {
        String openingTag = "<ul>";
        if(StringUtils.isNotEmpty(classNames)) {
            openingTag = String.format("<ul class="%s">", classNames);
        }
        return openingTag + StringUtils.join(listElements, "") + "</ul>";
    }
}

ul.additionalEvents {
        margin: 0;
        padding-left: 35px;
        padding-top: 10px;
        padding-bottom: 5px;
        color: gray;
        overflow: hidden;
     }