Java 日历 clone()方法及示例

Calendar类中的 clear() 方法是用来克隆一个日历对象的。它基本上是为这个对象创建一个浅层的副本。

语法

public Object clone()

参数： 该方法不接受任何参数。

返回值： 该方法不返回任何值。

下面的程序说明了日历类的clone()方法的工作原理：

例1 :

// Java Code to illustrate clone() Method  import java.util.Calendar;  public class CalendarClassDemo {    public static void main(String args[])    {        // Creating a calendar object        Calendar calndr1 = Calendar.getInstance();          // Displaying current calendar        System.out.println("Original calendar: "                           + calndr1.getTime());          // Cloning the original        Calendar calndr2 = (Calendar)calndr1.clone();          // Displaying the Copy        System.out.println("Cloned calendar: "                           + calndr2.getTime());    }}

输出:

Original calendar: Tue Feb 12 11:41:36 UTC 2019Cloned calendar: Tue Feb 12 11:41:36 UTC 2019

例2 :

// Java Code to illustrate clone() Method  import java.util.*;  public class CalendarClassDemo {    public static void main(String args[])    {        // Creating a calendar object        Calendar calndr1            = new GregorianCalendar(2018, 12, 2);          // Displaying current calendar        System.out.println("Original calendar: "                           + calndr1.getTime());          // Cloning the original        Calendar calndr2 = (Calendar)calndr1.clone();          // Displaying the Copy        System.out.println("Cloned calendar: "                           + calndr2.getTime());    }}

输出:

Original calendar: Wed Jan 02 00:00:00 UTC 2019Cloned calendar: Wed Jan 02 00:00:00 UTC 2019

**参考资料: **https://docs.oracle.com/javase/7/docs/api/java/util/Calendar.html#clone()