Add an element to specified index of Java ArrayList Example

This Java example shows how to add an element at specified index of Java ArrayList object using add method.

import java.util.ArrayList;

public class AddElementToSpecifiedIndexArrayListExample {

 public static void main(String[] args) {

  // create an ArrayList object
  ArrayList arrayList = new ArrayList();

  // Appends the specified element to the end of this list
  arrayList.add("1");
  arrayList.add("2");
  arrayList.add("3");

  System.out.println("ArrayList contains...");

  // display elements of ArrayList
  for (int index = 0; index < arrayList.size(); index++)
   System.out.println(arrayList.get(index));

  /**
   * To add an element at the specified index of ArrayList use void
   * add(int index, Object obj) method. This method inserts the specified
   * element at the specified index in the ArrayList.
   **/
  arrayList.add(1, "INSERTED ELEMENT");

  /**
   * Please note that add method DOES NOT overwrites the element
   * previously at the specified index in the list. It shifts the elements
   * to right side and increasing the list size by 1.
   **/

  System.out.println("After Insertion. ArrayList contains...");

  // display elements of ArrayList
  for (int index = 0; index < arrayList.size(); index++)
   System.out.println(arrayList.get(index));

 }
}

The output is



ArrayList contains...
 1
 2
 3
 After Insertion. ArrayList contains...
 1
 INSERTED ELEMENT
 2
 3