Object cloning Example in Java: create a list from existing list and have the new list modified for a single attribute.

Use case

You have a Book Class with several attributes, and you have to create a list from existing list and have the new list modified for a single attribute.

public class Book implements Cloneable{

private String bookName;

private String bookAuthor;

private String bookId;

public Book(String bookAuthor,String bookName,String bookId){

this.bookAuthor=bookAuthor;

this.bookName=bookName;

this.bookId=bookId;

}

public Book(){

}

public String getBookName() {

return bookName;

}

public void setBookName(String bookName) {

this.bookName = bookName;

}

public String getBookAuthor() {

return bookAuthor;

}

public void setBookAuthor(String bookAuthor) {

this.bookAuthor = bookAuthor;

}

public String getBookId() {

return bookId;

}

public void setBookId(String bookId) {

this.bookId = bookId;

}

protected Object clone() throws CloneNotSupportedException {

    Book clone=(Book)super.clone();

       

    return clone;

  }

}

import java.util.ArrayList;

import java.util.Iterator;

public class TestFunctionality {

/** You have a Book Class with several attributes, and you have to create a list from existing list and have the new list modified for a 

* single attribute.

*  

*  

**/

public static void main(String []arg){

ArrayList <Book>bookArrayList=new ArrayList<Book>();

ArrayList <Book>bookArrayList1=new ArrayList<Book>();

Book b1=new Book("Sachi","AA123","CoreJava");

Book b2=new Book("Sachii","AA1234","CoreJavaa");

Book b3=new Book("Sachiii","AA12345","CoreJavaaaa");

bookArrayList.add(b1);

bookArrayList.add(b2);

bookArrayList.add(b3);

Iterator<Book> bookListIterator = bookArrayList.iterator();

while (bookListIterator.hasNext()){

Book b=new Book();

try {

b=(Book) bookListIterator.next().clone();

System.out.println(b.getBookAuthor());

b.setBookAuthor("SACH");

bookArrayList1.add(b);

} catch (CloneNotSupportedException e) {

e.printStackTrace();

}

}

int length=bookArrayList1.size();

System.out.println("Length of the new list is " + length);

Iterator<Book> bookListIterator1 = bookArrayList1.iterator();

while (bookListIterator1.hasNext()){

System.out.println(bookListIterator1.next().getBookAuthor());

}

}

}