Can you do a forEach loop on an ArrayList?

Syntax of ArrayList forEach[]

The syntax of the forEach[] method is:

arraylist.forEach[Consumer action]

Here, arraylist is an object of the ArrayList class.

forEach[] Parameters

The forEach[] method takes a single parameter.

• action - actions to be performed on each element of the arraylist

forEach[] Return Value

The forEach[] method does not return any value.

Example: Java ArrayList forEach[]

import java.util.ArrayList; class Main { public static void main[String[] args] { // create an ArrayList ArrayList numbers = new ArrayList[]; // add elements to the ArrayList numbers.add[3]; numbers.add[4]; numbers.add[5]; numbers.add[6]; System.out.println["ArrayList: " + numbers]; System.out.print["Updated ArrayList: "]; // multiply each element by themselves // to compute the square of the number } }

Output

ArrayList: [3, 4, 5, 6] Updated ArrayList: 9 16 25 36

In the above example, we have created an arraylist named numbers. Notice the code,

numbers.forEach[[e] -> { e = e * e; System.out.print[e + " "]; }];

Here, we have passed the lambda expression as an argument to the forEach[] method. The lambda expression multiplies each element of the arraylist by itself and prints the resultant value.

To learn more about lambda expressions, visit Java Lambda Expressions.

Note: The forEach[] method is not the same as the for-each loop. We can use the Java for-each loop to iterate through each element of the arraylist.