I don't really understand your requirement. java.util.Date objects do not have an explicit time zone (the implicit one is UTC) so it seems you must be considering the date as a String. If one uses class SimpleDateFormat to parse this to a java.util.Date then one loses any time zone information that was explicit in the String so I suspect one has to parse the String oneself to extract the time zone. I would use a regular expression but they are not to everyone's taste.
Once you have the time zone extracted as a String then one can convert it to a TimeZone object using one of the static methods of class TimeZone.
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