Java - merge two ArrayLists into one

In this article, we would like to show you how to merge two ArrayLists into one in Java.

Quick solution:

myArrayList1.addAll(myArrayList2);

Practical example

In this example, we merge two ArrayLists into one using addAll() method.

import java.util.*;

public class Example {

    public static void main(String[] args) {
        List<String> letters1 = new ArrayList<>();

        letters1.add("A");
        letters1.add("B");
        letters1.add("C");

        List<String> letters2 = new ArrayList<>();

        letters2.add("D");
        letters2.add("E");
        letters2.add("F");

        letters1.addAll(letters2);

        System.out.println(letters1);
    }
}

Output:

[A, B, C, D, E, F]