Compare Date objects with compareTo method

With this example we are going to demonstrate how to compare Date objects with compareTo method of the Date class. In short, to compare a Date object with another you should:

  • Create a new Date object, using the Date() constructor, that allocates a Date object and initializes it so that it represents the time at which it was allocated, measured to the nearest millisecond.
  • Create a new Calendar, using getInstance() API method of Calendar, that gets a calendar using the default time zone and locale.
  • Use set(int field, int value) API method of Calendar to set a future value, e.g. year to the calendar object.
  • Use getTime() API method of Calendar. The method returns a Date object representing this Calendar’s time value, with millisecond offset from the January 1 1970 00:00:00.000 GMT.
  • Invoke compareTo(Date anotherDate) API method of Date, using the two Date objects. The method compares the two Dates for ordering and returns an int value, that is 0 if the argument Date is equal to the Date tat calls the method, a value less than 0 if this Date is before the Date argument; and a value greater than 0 if this Date is after the Date argument.

Let’s take a look at the code snippet that follows:

package com.javacodegeeks.snippets.core;

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

public class CompareDateObjectsWithCompareToMethod {
	public static void main(String[] args) {
		Date now = new Date();
		Calendar c = Calendar.getInstance();
		c.set(Calendar.YEAR, 2100);
		Date future = c.getTime();
		int d = now.compareTo(future);
		if (d<0) {
			System.out.println(now + " is before " + future);
		else if (d>0) {
			System.out.println(now + " is after " + future);
		else {
			System.out.println("Dates are equal");



Thu Oct 20 16:19:55 EEST 2011 is before Wed Oct 20 16:19:55 EEST 2100

This was an example of how to compare Date objects with compareTo(Date anotherDate) method of Date in Java.

Byron Kiourtzoglou

Byron is a master software engineer working in the IT and Telecom domains. He is an applications developer in a wide variety of applications/services. He is currently acting as the team leader and technical architect for a proprietary service creation and integration platform for both the IT and Telecom industries in addition to a in-house big data real-time analytics solution. He is always fascinated by SOA, middleware services and mobile development. Byron is co-founder and Executive Editor at Java Code Geeks.
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