Question

I have a date with the format 2012-02-02(yyyy-MM-dd).

For example if todays date is 2012-02-02 i need to add one and a half days to it which would make it 2012-02-03 06:00:00.0.

And if i have a number of dates of the following format 2012-02-03 06:30:00.0(yyyy-MM-dd HH:MM:SS.SSS) , i need to compare if all these dates are less than,greater than or equal to the date to which one and a half days were added above.

The comparison should also take care of the hours while comparing if the dates are less than,greater than or equal or equal to the other date and time.

How do i achieve the same.

Answer 1

well so i hope this will give you a clear idea. Calendar Documentation and SimpleDateFormat Documentaion

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String aDateString = "2012-02-02";
Date date = sdf.parse(aDateString);
System.out.println("reference date:"+date);

Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.add(Calendar.HOUR, 36);
System.out.println("added one and half days to reference date: "+cal.getTime());

String newDateString = "2012-02-03 06:30:00.0";
sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.S");
Date newDate = sdf.parse(newDateString);
System.out.println("new date to compare with reference date : "+newDate);

Calendar newCal = Calendar.getInstance();
newCal.setTime(newDate);

if(cal.after(newCal)){
    System.out.println("date is greater than reference that.");
}else if(cal.before(newCal)){
    System.out.println("date is lesser than reference that.");
}else{
    System.out.println("date is equal to reference that.");
}

OUTPUT :

reference date:Thu Feb 02 00:00:00 IST 2012
added one and half days to reference date: Fri Feb 03 12:00:00 IST 2012
new date to compare with reference date : Fri Feb 03 06:30:00 IST 2012
date is greater than reference that.