Comparing dates in Java

Question

I already read date functions but i cant think a best way to solve my problem.

I have a couple of dates from database which is String and i want to compare it to may current date. I am using the compareTo, but there is a problem using this function i guess it is because of i was comparing strings.

This is my function:

public int dateCompare(String today, String date2){
    return today.compareTo(date2);
}

And when i use it in sample dates:

dateCompare("04/19/2013","04/18/2013");

it returns 1, and when i change the value of first parameter to "04/20/2013" it still returns 1.

Please HELP...

Answer 1

Java has a Date object. You should be using that instead.

import java.util.Calendar;
import java.util.Date;

public class CompareDates {

    public static void main(String[] args) {
        // Create a calendar, this will default to today
        Calendar cal = Calendar.getInstance();
        // Subtract 1 day
        cal.add(Calendar.DATE, -1);
        // Compare the result (1)
        System.out.println(dateCompare(new Date(), cal.getTime()));
        // Add 2 days
        cal.add(Calendar.DATE, 2);
        // Compare the result (-1)
        System.out.println(dateCompare(new Date(), cal.getTime()));            
    }

    public static int dateCompare(Date today, Date date2) {
        System.out.println("Compare " + today + " with " + date2);
        return today.compareTo(date2);
    }
}

You could also just make use of the Date API and use before and after...

Date now = new Date();

Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, -1);
System.out.println(now + " isBefore " + cal.getTime() + " = " + now.before(cal.getTime()));
System.out.println(now + " isAfter " + cal.getTime() + " = " + now.after(cal.getTime()));
cal.add(Calendar.DATE, 2);
System.out.println(now + " isBefore " + cal.getTime() + " = " + now.before(cal.getTime()));
System.out.println(now + " isAfter " + cal.getTime() + " = " + now.after(cal.getTime()));