How to minus 45 days from from the current sysdate

[Ravi Kiran Va]

Hi ,

I have system Date Passed to the Java File , please Could anybody please tell me how can we minus 45 days from the current sysdate ??

[Campbell Ritchie]

Have you tried any of the methods in the Calendar class?

[rob michael]

Campbell is right - you should use the Calendar class.

Something like this should do the job (so you don't have to worry about the number of days in the month)

Calendar now = Calendar.getInstance();
		int daysOfYear = now.get(Calendar.DAY_OF_YEAR);
		if (daysOfYear>45){
			daysOfYear -= 45;
			now.set(Calendar.DAY_OF_YEAR, daysOfYear);
		}else{
			daysOfYear = 365 + daysOfYear - 45;
			now.set(Calendar.DAY_OF_YEAR, daysOfYear);
			now.set(Calendar.YEAR, now.get(Calendar.YEAR)-1);
		}

[Hauke Ingmar Schmidt]

Calendar has an add method, no need to do manual calculation: java.util.Calendar#add(int, int).

[rob michael]

Cool, I didn't realise that was the case, thats good to know

[Rob Spoor]

And of course, subtracting 45 days is the same as adding -45 days

[Jesper de Jong]

Also, rob michael, your code won't work correctly when the year has 366 days.

[Hauke Ingmar Schmidt]

Rob Spoor wrote:And of course, subtracting 45 days is the same as adding -45 days

At least the Javadoc is clear about this ^^.

[Campbell Ritchie]

why can't the rest of the Oracle/Sun documentation be that easy to understand?