We store a date in a sqlserver db table as varchar. When this is read in the java code as a String and then parsed to a Date, it gets read as UTC (java code is in servers that are in UT). And on reconverting the date to ET, it goes 4 hours behind. How do I handle storing the date in ET in this db column so it gets read as ET in the java code.
We are researching around offsets, but not understanding exactly what to do.
Varchar date in table 03/29/2019 23:23:03 //we want this date to be in ET
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
Date beginDate = sdf.parse("03/29/2019 23:23:03");
//The problem is when this code executes, the server is in UTC. So beginDate //is read as 03/29/2019 23:23:03 UTC instead of 03/29/2019 23:23:03 ET
Expected 03/29/2019 23:23:03 ET Actual 03/29/2019 23:23:03 UTC
First, you need to be aware that a Date object doesn't have a time zone at all. It's just an instant in time. So even when you've parsed the value correctly, it'll represent the right instant in time, but you may need to convert it back to Eastern Time later on.
Second, you need to be aware that storing values like this introduces ambiguity - if you store a value of (say) 11/03/2019 01:30, that local time occurs twice - once before the daylight saving transition and once afterwards. If you're always storing times in the past, you should at least consider storing UTC instead - although that's not always the right answer, particularly not if you're storing future date/time values.
For the parsing part, you just need to set the time zone in the Calendar used by SimpleDateFormat. For example:
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss", Locale.US);
sdf.setTimeZone(TimeZone.getTimeZone("America/New_York");
Date beginDate = sdf.parse("03/29/2019 23:23:03");
Finally, I'd strongly advise you to start migrating your code to use java.time if at all possible. It's a much nicer API than the java.util.Date etc API.