@Override
    public String toString() {
        return "TimelineEvent{"
                + "id=" + id
                + ", data=" + data
                + ", startDate=" + startDate
                + ", endDate=" + endDate
                + ", editable=" + editable
                + ", group='" + group + '\''
                + ", subgroup='" + subgroup + '\''
                + ", styleClass='" + styleClass + '\''
                + '}';
    }
The type of the item. Can be 'box' (default), 'point', 'range', or 'background'.
<p>
Types 'box' and 'point' need a start date, the types 'range' and 'background' needs both a start and end date.
primefaces/src/main/java/org/primefaces/model/timeline/TimelineEvent.java