阅读下面程序，说明SimpleDateFormat类中的两个方法的作用：package exer;//"三天打渔，两天晒网"import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Date;public class GetFish {public static void main(String[] args) {String date1 = "1990/1/1"; // 开始“三天打鱼两天晒网”的日期String date2 = "1990/1/10"; // 手动输入的日期long day = getQuot(date1, date2);// 传入值计算时间差if ((day + 1) % 5 == 0 || (day + 1) % 5 == 4) {System.out.println("今天是休息日，可以晒晒网");} else {System.out.println("今天要工作，打鱼了！");}}public static long getQuot(String time1, String time2) {long dayDistance = 0;SimpleDateFormat ft = new SimpleDateFormat("yyyy/MM/dd");try {Date date1 = ft.parse(time1);Date date2 = ft.parse(time2);dayDistance = date2.getTime() - date1.getTime();dayDistance = dayDistance / 1000 / 60 / 60 / 24;} catch (ParseException e) {e.printStackTrace();}return dayDistance;}}