java 日期时分秒 相减 java中时间相减

package org.songbai.fore.strategy.controller;

import java.text.ParseException;  
import java.text.SimpleDateFormat;  
import java.util.Date;  
  
  
/**
 * 描述：Java计算时间差（两个时间相减）
 */
public class demo {  
  
    public static void main(String[] args) throws ParseException {  
        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  
        try  
        {  
          Date d1 = df.parse("2004-03-26 13:31:00");  
          Date d2 = df.parse("2004-03-26 14:31:00");  
          long diff = d1.getTime() - d2.getTime();//这样得到的差值是微秒级别  
          long days = diff / (1000 * 60 * 60 * 24);  
       
          long hours = (diff-days*(1000 * 60 * 60 * 24))/(1000* 60 * 60);  
          long minutes = (diff-days*(1000 * 60 * 60 * 24)-hours*(1000* 60 * 60))/(1000* 60);  
          System.out.println(""+days+"天"+hours+"小时"+minutes+"分");  
        }catch (Exception e)  
        {  
        }  
    }  
  
}