Java, converting Date to String and back produced wrong Date
date-format, java, simpledateformat
Solution
Probably because of the timezone change in Singapore on 1982 (+ 30 minutes).
http://www.timeanddate.com/worldclock/timezone.html?n=236&syear=1980
The SimpleDateFormat take the SGT as UTC+8 when parsing the date, and convert it to UTC+7.5, which is the SGT before 1982. Hence the date is off by 30 minutes.
Problem
I am trying to convert a `Date` to `String` and then back again to `Date`. However I found out that the final date is different from the original date, what gives? ``` //1975-06-20 Calendar cal = Calendar.getInstance(); cal.set(Calendar.YEAR, 1975); cal.set(Calendar.MONTH, 5); cal.set(Calendar.DAY_OF_MONTH, 20); cal.set(Calendar.HOUR, 0); cal.set(Calendar.MINUTE, 0); cal.set(Calendar.SECOND, 0); System.out.println(cal); Date originalDate = cal.getTime(); System.out.println("Date 1: " + originalDate.toString()); SimpleDateFormat sdf = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy"); Date date = sdf.parse(originalDate.toString()); System.out.println("Date 2: " + date.toString()); ``` The output from the above code is: ``` cal: java.util.GregorianCalendar[time=?,areFieldsSet=false,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Asia/Singapore",offset=28800000,dstSavings=0,useDaylight=false,transitions=9,lastRule=null],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=1975,MONTH=5,WEEK_OF_YEAR=26,WEEK_OF_MONTH=5,DAY_OF_MONTH=20,DAY_OF_YEAR=179,DAY_OF_WEEK=4,DAY_OF_WEEK_IN_MONTH=4,AM_PM=1,HOUR=0,HOUR_OF_DAY=16,MINUTE=0,SECOND=0,MILLISECOND=333,ZONE_OFFSET=28800000,DST_OFFSET=0] Date 1: Fri Jun 20 12:00:00 SGT 1975 Date 2: Fri Jun 20 11:30:00 SGT 1975 ```