计算时间差（天，小时，分钟）

package com.example.面向对象1;


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

public class 计算时间差 {


    public static void calculateTimeDifferenceBySimpleDateFormat() throws ParseException, ParseException {
        SimpleDateFormat simpleFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm");
        /*天数差*/
        Date fromDate1 = simpleFormat.parse("2018-03-01 12:00");
        Date toDate1 = simpleFormat.parse("2018-03-12 12:00");
        long from1 = fromDate1.getTime();
        long to1 = toDate1.getTime();
        int days = (int) ((to1 - from1) / (1000 * 60 * 60 * 24));
        System.out.println("两个时间之间的天数差为：" + days);

        /*小时差*/
        Date fromDate2 = simpleFormat.parse("2018-03-01 12:00");
        Date toDate2 = simpleFormat.parse("2018-03-12 12:00");
        long from2 = fromDate2.getTime();
        long to2 = toDate2.getTime();
        int hours = (int) ((to2 - from2) / (1000 * 60 * 60));
        System.out.println("两个时间之间的小时差为：" + hours);

        /*分钟差*/
        Date fromDate3 = simpleFormat.parse("2018-03-01 12:00");
        Date toDate3 = simpleFormat.parse("2018-03-12 12:00");
        System.out.println("toDate3"+toDate3);
        long from3 = fromDate3.getTime();
        long to3 = toDate3.getTime();
        int minutes = (int) ((to3 - from3) / (1000 * 60));
        System.out.println("两个时间之间的分钟差为：" + minutes);
    }


    public static void main(String[] args) throws ParseException {
        calculateTimeDifferenceBySimpleDateFormat();

    }

}