insert element in list java code example

Example 1: ArrayList add(int index, E element) method in java

import java.util.ArrayList;
public class ArrayListAddMethodExample
{
   public static void main(String[] args)
   {
      // creating an empty ArrayList with initial capacity
      ArrayList<Integer> al = new ArrayList<Integer>(6);
      al.add(12);
      al.add(14);
      al.add(16);
      al.add(18);
      al.add(20);
      // adding element 15 at fourth position
      al.add(3, 15);
      for(Integer number : al)
      {
         System.out.println("Number: " + number);
      }
   }
}

Example 2: java append to list

package com.journaldev.examples;

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

public class ListAddExamples {

	public static void main(String[] args) {

		List<String> vowels = new ArrayList<>();

		vowels.add("A"); // [A]
		vowels.add("E"); // [A, E]
		vowels.add("U"); // [A, E, U]

		System.out.println(vowels); // [A, E, U]

		vowels.add(2, "I"); // [A, E, I, U]
		vowels.add(3, "O"); // [A, E, I, O, U]

		System.out.println(vowels); // [A, E, I, O, U]
	}
}