ArrayList forEach() Method in Java

Last Updated : 11 Jul, 2025

In Java, the ArrayList.forEach() method is used to iterate over each element of an ArrayList and perform certain operations for each element in ArrayList.

Example 1: Here, we will use the forEach() method to print all elements of an ArrayList of Strings.

Java

// Java program to demonstrate the use of forEach()  // with an ArrayList of Strings import java.util.ArrayList; public class GFG {  public static void main(String[] args) {  // Create an ArrayList of Strings  ArrayList<String> s = new ArrayList<>();  s.add("Cherry");  s.add("Blueberry");  s.add("Strawberry");  // Use forEach() to print each fruit  s.forEach(System.out::println);  } }

Output

Cherry Blueberry Strawberry

Explanation: In the above example, we use the forEach() method with a method reference (System.out::println) to print each element in the ArrayList.

Syntax of ArrayList.forEach() Method

public void forEach(Consumer<? super E> action)

Parameter: action: A functional interface "Consumer" that specifies the action to be performed for each element in the ArrayList. It accepts a single parameter and does not return any value.

Exception: This method throws NullPointerException if the specified action is null.

Other Examples of forEach() Method

Example 2: Here, we will use the forEach() method with a lambda expression to print the square of each element in an ArrayList of Integers.

Java

// Java program to demonstrate  // custom actions using forEach() import java.util.ArrayList; public class GFG {  public static void main(String[] args) {  // Create an ArrayList of Integers  ArrayList<Integer> n = new ArrayList<>();  n.add(2);  n.add(3);  n.add(4);  // Use forEach() to print the   // square of each number  n.forEach(num -> System.out.println(num * num));  } }

Output

4 9 16

Example 3: Here, we will use the forEach() method with a conditional statement to filter and print eligible elements of an ArrayList of Integers.

Java

// Java program to demonstrate  // conditional actions using forEach() import java.util.ArrayList; public class GFG {  public static void main(String[] args) {  // Create an ArrayList of Integers  ArrayList<Integer> a = new ArrayList<>();  a.add(24);  a.add(18);  a.add(10);  // Use forEach() to print   // ages that are 18 or above  a.forEach(age -> {  if (age >= 18) {  System.out.println("Eligible age: " + age);  }  });  } }

Output

Eligible age: 24 Eligible age: 18

Explanation: In the above example, we use the forEach() method with a lambda expression and conditional logic to filter and print elements based on a condition.