How to Convert an ArrayList Containing Integers to Primitive Int Array?

Last Updated : 09 Feb, 2024

In Java, ArrayList is the pre-defined class of the Java Collection Framework. It is part of the java.util package. ArrayList can be used to add or remove an element dynamically in the Java program. It can be snipped dynamically based on the elements added or removed into the ArrayList.

In this article, we will discuss how to convert an ArrayList containing Integers to a primitive int array.

Methods to Convert an ArrayList containing Integers to Primitive Int Array

Two methods are mostly used to implement the ArrayList integers convert into a primitive integer array.

add(): It is a pre-defined method of the ArrayList that can be used to add the elements into the ArrayList.
get(): it is also an in-built method and it can be used to retrieve the elements into the ArrayList.

Program to Convert an ArrayList Containing Integers to Primitive Int Array in Java

Java

// Java Program to convert an ArrayList // Containing Integers to primitive int array import java.util.ArrayList;  //ArrayList convert into the primitive int array public class GFGexample  {     //main method     public static void main(String[] args)      {         // Create the ArrayList named as arrayList         ArrayList<Integer> arrayList = new ArrayList<>();         arrayList.add(10);         arrayList.add(50);         arrayList.add(100);         arrayList.add(150);          // Convert ArrayList<Integer> to int[]         int[] intArray = convertToIntArray(arrayList);          // print the result         System.out.print("Original ArrayList: " + arrayList);         System.out.println("\nConverted int array: " + java.util.Arrays.toString(intArray));     }      // method to convert ArrayList<Integer> to int[]     private static int[] convertToIntArray(ArrayList<Integer> list)      {         int[] intArray = new int[list.size()];                  for (int i = 0; i < list.size(); i++)          {             intArray[i] = list.get(i);         }          return intArray;     } }

Output

Original ArrayList: [10, 50, 100, 150]  Converted int array: [10, 50, 100, 150]