The date is a more simplistic class and is essentially there for slow adaptability reasons. If you need to set precise dates or do date arithmetic, try e a Calendar. Calendars also manage localization. The early date manipulation functions of Date have since been opposed.
I manage to use both times in milliseconds as a long (or Long, as relevant) or Calendar when there is a choice.
Both Date and Calendar are uncertain, which tends to perform problems when applying either in an API.