Java CopyOnWriteArrayList clone()方法

CopyOnWriteArrayList 的 clone() 方法返回列表的一个浅层副本。该浅层拷贝包含相同索引的完全相同的元素。

语法

public Object clone()

参数： 该函数不接受任何参数。

返回值： 该函数返回列表的一个克隆。

下面的程序说明了上述函数。

程序1 :

// Java Program to illustrate the 
// CopyOnWriteArrayList clone() method in Java
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create object of CopyOnWriteArrayList
        CopyOnWriteArrayList<Integer> ArrLis
            = new CopyOnWriteArrayList<Integer>();
  
        // Add elements
        ArrLis.add(32);
        ArrLis.add(67);
        ArrLis.add(98);
        ArrLis.add(100);
  
        // print CopyOnWriteArrayList
        System.out.println("CopyOnWriteArrayList: " 
                                           + ArrLis);
  
        // clone of the arraylist
        System.out.println("CopyOnWriteArrayList: "
                                    + ArrLis.clone());
    }
}

输出。

CopyOnWriteArrayList: [32, 67, 98, 100]
CopyOnWriteArrayList: [32, 67, 98, 100]

程序2

// Java Program to illustrate the 
// CopyOnWriteArrayList clone() method in Java
  
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create object of CopyOnWriteArrayList
        CopyOnWriteArrayList<String> ArrLis
            = new CopyOnWriteArrayList<String>();
  
        // Add elements
        ArrLis.add("gopal");
        ArrLis.add("gfg");
        ArrLis.add("jgec");
        ArrLis.add("sudo");
  
        // print CopyOnWriteArrayList
        System.out.println("CopyOnWriteArrayList: " 
                                          + ArrLis);
  
        // clone of the arraylist
        System.out.println("CopyOnWriteArrayList: " 
                                  + ArrLis.clone());
    }
}

输出。

CopyOnWriteArrayList: [gopal, gfg, jgec, sudo]
CopyOnWriteArrayList: [gopal, gfg, jgec, sudo]

参考资料: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CopyOnWriteArrayList.html#clone-