This is an example of how to replace elements in an ArrayList using index. Replacing elements in an ArrayList using index implies that you should:

• Create a new ArrayList.
• Populate the arrayList with elements, using add(E e) API method of ArrayList.
• Use set(int index, Object obj) method of ArrayList, using a specified element and a specified index. The method replaces an element at the specified index of the arrayList with the given element. It returns the element previously at the specified position.

Let’s take a look at the code snippet that follows:

package com.javacodegeeks.snippets.core;
 
import java.util.ArrayList;
 
public class ReplaceElementArrayListIndex {
 
  public static void main(String[] args) {

    // Create an ArrayList and populate it with elements
    ArrayList arrayList = new ArrayList();
    arrayList.add("element_1");
    arrayList.add("element_2");
    arrayList.add("element_3");
 
    /*

Use Object set(int index, Object obj) operation to replace an element at 

the specified index of ArrayList. It returns the element previously at 

the specified position.
    */
    arrayList.set(1,"element_4");
 
    System.out.println("Elements in ArrayList :");
    for(int i=0; i < arrayList.size(); i++)

System.out.println(arrayList.get(i));
 
  }
}

Output:

Elements in ArrayList :
element_1
element_4
element_3

 
This was an example of how to replace elements in an ArrayList using index in Java.