Java GregorianCalendar clone()用法及代碼示例

GregorianCalendar類的java.util.GregorianCalendar.clone()方法用於創建一個新對象，並將該GregorianCalendar實例的所有內容複製到新對象中。

用法:

public Object clone()

參數：該函數不接受任何參數。

返回值：此函數返回此對象的副本。

例子：

Input: Mon Jul 23 14:35:27 UTC 2018
Output: Mon Jul 23 14:35:27 UTC 2018

Input: Current Date and Time is Mon Jul 23 14:35:27 UTC 2018
       cal1.add((GregorianCalendar.MONTH), -7);
       cal1.clone();
Output: Sat Dec 23 14:36:42 UTC 2017

以下示例程序旨在說明java.util.GregorianCalendar.clone()方法：
示例1:

// Java Program to illustrate GregorianCalendar.clone() 
// function  
  
import java.io.*; 
import java.util.*; 
  
class GFG { 
    public static void main(String[] args) 
    { 
  
        // Creating a new calendar 
        GregorianCalendar cal = (GregorianCalendar) 
                   GregorianCalendar.getInstance(); 
  
        // Display the date and time 
        System.out.println("Date and Time in"
                +" cal object : "+ cal.getTime()); 
  
        GregorianCalendar newcalender =  
                          new GregorianCalendar(); 
  
        // Cloning the object 
        newcalender = (GregorianCalendar)cal.clone(); 
  
        // Display date and time 
        System.out.println("Date and Time in"+ 
        " newcalender object : "+ newcalender.getTime()); 
    } 
}

輸出：

Date and Time in cal object : Fri Aug 03 11:01:24 UTC 2018
Date and Time in newcalender object : Fri Aug 03 11:01:24 UTC 2018

示例2:

// Java Program to illustrate  
// GregorianCalendar.clone() 
// function  
  
import java.io.*; 
import java.util.*; 
  
class GFG { 
    public static void main(String[] args) 
    { 
  
        // Creating a new calendar 
        GregorianCalendar cal1, cal2; 
  
        cal1 = (GregorianCalendar)GregorianCalendar. 
                                     getInstance(); 
  
        // Display the current date and time 
        System.out.println("Current Date and Time : "
                                   + cal1.getTime()); 
        // Modifying the current date and time 
        cal1.add((GregorianCalendar.MONTH), 2); 
  
        // Cloning the object 
        cal2 = (GregorianCalendar)cal1.clone(); 
  
        // Display date and time 
        System.out.println("New Date and Time : "
                           + cal2.getTime()); 
    } 
}

輸出：

Current Date and Time : Fri Aug 03 11:01:27 UTC 2018
New Date and Time : Wed Oct 03 11:01:27 UTC 2018

參考： https://docs.oracle.com/javase/7/docs/api/java/util/GregorianCalendar.html#clone()

相關用法

注：本文由純淨天空篩選整理自RICHIK BHATTACHARJEE大神的英文原創作品 GregorianCalendar clone() Method in Java。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。