Java日历类Calendar

package com.leo;

import java.util.Calendar;
import java.util.Date;

public class CalendarTest {
    public static void main(String[] args) {
        // 1.实例化
        Calendar calendar = Calendar.getInstance();

        // 2.常用方法
        // get()
        int days = calendar.get(Calendar.DAY_OF_MONTH);
        System.out.println(days);
        System.out.println(Calendar.DAY_OF_YEAR);

        // set()
        calendar.set(Calendar.DAY_OF_MONTH, 22);
        days = calendar.get(Calendar.DAY_OF_MONTH);
        System.out.println(days);

        // add()
        calendar.add(Calendar.DAY_OF_MONTH, -3);
        days = calendar.get(Calendar.DAY_OF_MONTH);
        System.out.println(days);

        // getTime()
        Date date = calendar.getTime();
        System.out.println(date);

        // setTime()
        Date date1 = new Date();
        calendar.setTime(date1);
        System.out.println(Calendar.DAY_OF_MONTH);
    }

}