java计算时间差的几种方法

用JAVA计算日期，时间差的几种方法
1. 手工计算
2.采用一个三方的jar包(Joda time library)
3. 利用TimeUnit类(java.util.concurrent 包中)

方法一:手工计算

import java.text.SimpleDateFormat;
import java.util.Date;
 
public class DateDifferentExample {
 
	public static void main(String[] args) {
 
		String dateStart = "01/14/2012 09:29:58";
		String dateStop = "01/15/2012 10:31:48";
 
		//HH converts hour in 24 hours format (0-23), day calculation
		SimpleDateFormat format = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
 
		Date d1 = null;
		Date d2 = null;
 
		try {
			d1 = format.parse(dateStart);
			d2 = format.parse(dateStop);
 
			//in milliseconds
			long diff = d2.getTime() - d1.getTime();
 
			long diffSeconds = diff / 1000 % 60;
			long diffMinutes = diff / (60 * 1000) % 60;
			long diffHours = diff / (60 * 60 * 1000) % 24;
			long diffDays = diff / (24 * 60 * 60 * 1000);
 
			System.out.print(diffDays + " days, ");
			System.out.print(diffHours + " hours, ");
			System.out.print(diffMinutes + " minutes, ");
			System.out.print(diffSeconds + " seconds.");
 
		} catch (Exception e) {
			e.printStackTrace();
		}
 
	}
 
}

1 days, 1 hours, 1 minutes, 50 seconds.

import java.text.SimpleDateFormat;
import java.util.Date;
 
import org.joda.time.DateTime;
import org.joda.time.Days;
import org.joda.time.Hours;
import org.joda.time.Minutes;
import org.joda.time.Seconds;
 
public class JodaDateDifferentExample {
 
  public static void main(String[] args) {
 
	String dateStart = "01/14/2012 09:29:58";
	String dateStop = "01/15/2012 10:31:48";
 
	SimpleDateFormat format = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
 
	Date d1 = null;
	Date d2 = null;
 
	try {
		d1 = format.parse(dateStart);
		d2 = format.parse(dateStop);
 
		DateTime dt1 = new DateTime(d1);
		DateTime dt2 = new DateTime(d2);
 
		System.out.print(Days.daysBetween(dt1, dt2).getDays() + " days, ");
		System.out.print(Hours.hoursBetween(dt1, dt2).getHours() % 24 + " hours, ");
		System.out.print(Minutes.minutesBetween(dt1, dt2).getMinutes() % 60 + " minutes, ");
		System.out.print(Seconds.secondsBetween(dt1, dt2).getSeconds() % 60 + " seconds.");
 
	 } catch (Exception e) {
		e.printStackTrace();
	 }
 
  }
 
}

1 days, 1 hours, 1 minutes, 50 seconds.

long diffSeconds = diff / 1000 % 60;
long diffMinutes = diff / (60 * 1000) % 60;

long diffSeconds = TimeUnit.MILLISECONDS.toSeconds(diff) % 60;
long diffMinutes = TimeUnit.MILLISECONDS.toMinutes(diff) % 60;
long diffHours = TimeUnit.MILLISECONDS.toHours(diff) % 24;
long diffDays = TimeUnit.MILLISECONDS.toDays(diff);