Tip: a (programming) question consisting of one sentence is never ever a question that can be answered. It simply does not contain enough information.
In this case: what exactly is a "date format"? Some random string somewhere?
java.util.Date is ALWAYS utc.
The only 'timezone' in relation to that is how you create/parse data from other sources.
Normally one uses SimpleDateFormat to facilitate that.
There are other methods such as jdbc drivers which are used to create/output from a database.
Timestamps always have an implicit or explicit timezone associated with it. If you have a data source of a timestamp (date/time) such as text which does not have an explicit timezone then you MUST determine what the timezone is. Doing that might involve asking/insisting that the source provide the information either with the text or provide written documentation stating what the timezone is.