How does the 'add' method in ArrayLists handle insertion at a specific index?

In Java, the add(int index, E element) method of the ArrayList class allows you to insert an element at a specific index. When you use this method, the following happens:

1. Shifting Elements: The elements that are currently at and after the specified index are shifted to the right (i.e., their indices are increased by one) to make room for the new element.

2. Inserting the Element: The specified element is then inserted at the given index.

Here’s an example of how to use the add method to insert an element at a specific index in an ArrayList:

import java.util.ArrayList;

public class Main {
    public static void main(String[] args) {
        ArrayList<String> list = new ArrayList<>();
        list.add("Apple");
        list.add("Banana");
        list.add("Cherry");

        System.out.println("Before insertion: " + list);

        // Insert "Orange" at index 1
        list.add(1, "Orange");

        System.out.println("After insertion: " + list);
    }
}

Output:

Before insertion: [Apple, Banana, Cherry]
After insertion: [Apple, Orange, Banana, Cherry]

In this example, "Orange" is inserted at index 1, and "Banana" is shifted to index 2.