I have a Java app that needs to be cognizant of the time zone. When I take a Unix epoch time and try to convert it into a timestamp to use for an Oracle SQL call, it is getting the correct timezone, but the timezone "useDaylightTime" value is not correct, i.e., it is currently returning "true", when we are NOT in DST (I am in Florida in TZ "America/New_York").

This is running on Red Hat Linux Enterprise 6, and as far as I can tell, it is correctly set up for the timezone, e.g. 'date' returns: Wed Nov 28 12:30:12 EST 2012

I can also see, using the 'zdump' utility, that the current value for 'isdst' is 0.

My Java version is 1.6.0_31.

I have Googled this and seen the numerous issues this has caused, but many of them simply say to set the TZ manually, but my issue is not the TZ, but the fact that the default TZ has the "isDaylight" set to 'true'. I believe this is causing my query to return data that is one hour off (I can see that it is).

Here is a simple code piece I have run to try and reproduce this in the simplest way possible:

public class TZdefault {

    public static void main(String[] args) throws IOException {

            long startTime = System.currentTimeMillis()/1000;

            Calendar start = Calendar.getInstance();
            start.setTimeInMillis(startTime);

            start.setTimeZone(TimeZone.getDefault());

            System.out.println("Start UTC: " + start + "ms: " + start.getTimeInMillis());
            System.out.println("use daylight: " + start.getTimeZone().useDaylightTime());

    } // end main


}  // end class

One final thing. If in my code I set the TZ to "EST", it of course does return a TZ with 'isDaylight' set to False. But that is not a good solution.

I wanted to add some more detail that I had been hoping to hide.

I have records in an Oracle 11g database that use TIMESTAMP with TIMEZONE fields. I am simply doi

java timezone dst
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