1 import java.util.Calendar;
 2 import java.util.Date;
 3 
 4 /**
 5  *Calendar類(抽象類)日曆的使用
 6  *
 7  * @author fu jingchao
 8  * @creat 2021/11/7-17:10
 9  */
10 public class CalendarTest {
11     public static void main(String[] args) {
12         //1.例項化
13         //方式一：建立其子類(GregorianCalendar)的物件
14         //
 
方式二：呼叫其靜態方法getInstance()
15         Calendar calendar = Calendar.getInstance();
16         System.out.println(calendar.getClass());//class java.util.GregorianCalendar
17 
18         //2.常用方法
19         //1.get()
20         int days = calendar.get(Calendar.DAY_OF_MONTH);
21         System.out.println(days);
 
22         System.out.println(calendar.get(Calendar.DAY_OF_WEEK));
23 
24         //2.set()
25         calendar.set(Calendar.DAY_OF_MONTH,22);
26         days = calendar.get(Calendar.DAY_OF_MONTH);
27         System.out.println(days);
28 
29         //3.add()
30         calendar.add(Calendar.DAY_OF_MONTH,3);//
 
如果是負數，就是減幾天
31         days = calendar.get(Calendar.DAY_OF_MONTH);
32         System.out.println(days);
33 
34         //4.getTime():日曆類---->Date
35         Date date = calendar.getTime();
36         System.out.println(date);//Sat Dec 25 16:58:11 CST 2021
37 
38         //5.setTime():Date---->日曆類
39         Date date1 = new Date();
40         calendar.setTime(date1);
41         days = calendar.get(Calendar.DAY_OF_MONTH);
42         System.out.println(days);
43 
44         System.out.println(calendar.get(Calendar.MONTH));//注意：獲取月份時，一月是0.二月是1，...，12月是11
45 
46     }
47 
48 }