javacalendarjava-ee-7gregorian-calendar

How to convert Gregorian string to Gregorian Calendar?

I have to compute something based on the Calendar's date, but I am receiving the complete Gregorian Calendar's String value.

Eg i/p received {may be - "new GregorianCalendar().toString()"} as String :- java.util.GregorianCalendar[time=1410521241348,areFieldsSet=true,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Europe/London",offset=0,dstSavings=3600000,useDaylight=true,transitions=242,lastRule=java.util.SimpleTimeZone[id=Europe/London,offset=0,dstSavings=3600000,useDaylight=true,startYear=0,startMode=2,startMonth=2,startDay=-1,startDayOfWeek=1,startTime=3600000,startTimeMode=2,endMode=2,endMonth=9,endDay=-1,endDayOfWeek=1,endTime=3600000,endTimeMode=2]],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=2014,MONTH=8,WEEK_OF_YEAR=37,WEEK_OF_MONTH=2,DAY_OF_MONTH=12,DAY_OF_YEAR=255,DAY_OF_WEEK=6,DAY_OF_WEEK_IN_MONTH=2,AM_PM=1,HOUR=0,HOUR_OF_DAY=12,MINUTE=27,SECOND=21,MILLISECOND=348,ZONE_OFFSET=0,DST_OFFSET=3600000]

I want to extract the Calendar's date value to process further computation.

Solution

  • Other answers are too complicated or wrong. The following will give you the milliseconds since the epoch, which is a universal timestamp that you can easily convert to most time representation classes, including Calendar or Date: 

    Pattern gregorianPattern = Pattern.compile("^java.util.GregorianCalendar\\[time=(\\d+).*"); 

Matcher matcher = gregorianPattern.matcher(param);
if(matcher.matches()) {
    return Long.parseLong(matcher.group(1));
}