Java clone method example

Java clone method is used to present the duplication of object in the Java programming language. The Java objects are manipulated through reference variables, we don't have any way to copy an object in java. The clone ( ) is a constructor that call the clone method of super class in order to get the copy of object.

Understand with Example

In this Tutorial we want to describe you a code that help you in understanding a ClonemethodExample.For this we have a primitive class int,The int constructor return you the object of this class by passing the int value a assigned to i. The increase method ( ) return you increment value of i. The String toString ( ) return you the string representation of integer. The ClonemethodExample class include main method that create array list object 'list'. The for loop run the loop and the list object call the add method ( ) and add integer variable to it. Finally the println print the list.

1)Clone ( ) method - This method return you the typecasting that needed to assign the generic object to a reference of my class object type.

The for loop include the list object that call the iterator method and return the Iterator object.

The Iterator object e iterate the value from the list and call the next method( ).

2)next ( )method - This method return you the next element in the list if it is present in list

Finally the println print the list of clone value.

ClonemethodExample.java

import java.util.*;



class Int {



    private int i;



    public Int(int a) {

        i = a;

    }



    public void increase() {

        i++;

    }



    public String toString() {

        return Integer.toString(i);

    }

}



public class ClonemethodExample {



    public static void main(String[] args) {

        ArrayList list = new ArrayList();



        for (int i = 0; i < 5; i++) {

            list.add(new Int(i));

        }

        System.out.println("List is : " + list);



        ArrayList list1 = (ArrayList) list.clone();





        for (Iterator e = list1.iterator(); e.hasNext();) {

            ((Int) e.next()).increase();

        }

        System.out.println("List after cloning is: " + list);

    }

}

Output of the program


List is : [0, 1, 2, 3, 4]

List after cloning is: [1, 2, 3, 4, 5]

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