Copying and Cloning Lists: public Object clone() : ArrayList « Collections « Java Tutorial

1. Java Tutorial
2. Collections
3. ArrayList

1. When you call the clone() method of an ArrayList, a shallow copy of the list is created.
2. The new list refers to the same set of elements as the original.
3. It does not duplicate those elements.
4. Since clone() is a method of the ArrayList class and not the List (or Collection) interface, you must call clone() on a reference to the class, not the interface.

import java.util.ArrayList;
import java.util.List;

public class MainClass {
  public static void main(String[] a) {

    List list = new ArrayList();
    list.add("A");

    List list2 = ((List) ((ArrayList) list).clone());

    System.out.println(list);
    System.out.println(list2);

    list.clear();

    System.out.println(list);
    System.out.println(list2);
  }
}

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