java日期比较工具类

package com.net.util;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

import com.sun.org.apache.xerces.internal.impl.xpath.regex.ParseException;
/**
 * 日期比较工具类
 * @author zhangdi
 *
 */
public class DateUtil {
    /** 
     * 两个时间之间相差距离多少天 
     * @param one 时间参数 1： 
     * @param two 时间参数 2： 
     * @return 相差天数 
     */  
    public static long getDistanceDays(String str1, String str2) throws Exception{  
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd");  
        Date one;  
        Date two;  
        long days=0;  
        try {  
            one = df.parse(str1);  
            two = df.parse(str2);  
            long time1 = one.getTime();  
            long time2 = two.getTime();  
            long diff ;  
            if(time1<time2) {  
                diff = time2 - time1;  
            } else {  
                diff = time1 - time2;  
            }  
            days = diff / (1000 * 60 * 60 * 24);  
        } catch (ParseException e) {  
            e.printStackTrace();  
        }  
        return days;  
    }  
      
    /** 
     * 两个时间相差距离多少天多少小时多少分多少秒 
     * @param str1 时间参数 1 格式：1990-01-01 12:00:00 
     * @param str2 时间参数 2 格式：2009-01-01 12:00:00 
     * @return long[] 返回值为：{天, 时, 分, 秒} 
     * @throws java.text.ParseException 
     */  
    public static long[] getDistanceTimes(String str1, String str2) throws java.text.ParseException {  
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  
        Date one;  
        Date two;  
        long day = 0;  
        long hour = 0;  
        long min = 0;  
        long sec = 0;  
        try {  
            one = df.parse(str1);  
            two = df.parse(str2);  
            long time1 = one.getTime();  
            long time2 = two.getTime();  
            long diff ;  
            if(time1<time2) {  
                diff = time2 - time1;  
            } else {  
                diff = time1 - time2;  
            }  
            day = diff / (24 * 60 * 60 * 1000);  
            hour = (diff / (60 * 60 * 1000) - day * 24);  
            min = ((diff / (60 * 1000)) - day * 24 * 60 - hour * 60);  
            sec = (diff/1000-day*24*60*60-hour*60*60-min*60);  
        } catch (ParseException e) {  
            e.printStackTrace();  
        }  
        long[] times = {day, hour, min, sec};  
        return times;  
    }  
    /** 
     * 两个时间相差距离多少天多少小时多少分多少秒 
     * @param str1 时间参数 1 格式：1990-01-01 12:00:00 
     * @param str2 时间参数 2 格式：2009-01-01 12:00:00 
     * @return String 返回值为：xx天xx小时xx分xx秒 
     * @throws java.text.ParseException 
     */  
    public static String getDistanceTime(String str1, String str2) throws java.text.ParseException {  
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  
        Date one;  
        Date two;  
        long day = 0;  
        long hour = 0;  
        long min = 0;  
        long sec = 0;  
        try {  
            one = df.parse(str1);  
            two = df.parse(str2);  
            long time1 = one.getTime();  
            long time2 = two.getTime();  
            long diff ;  
            if(time1<time2) {  
                diff = time2 - time1;  
            } else {  
                diff = time1 - time2;  
            }  
            day = diff / (24 * 60 * 60 * 1000);  
            hour = (diff / (60 * 60 * 1000) - day * 24);  
            min = ((diff / (60 * 1000)) - day * 24 * 60 - hour * 60);  
            sec = (diff/1000-day*24*60*60-hour*60*60-min*60);  
        } catch (ParseException e) {  
            e.printStackTrace();  
        }  
        return day + "天" + hour + "小时" + min + "分" + sec + "秒";  
    }  
}