<dependencies> <dependency> <groupId>org.eclipse.collections</groupId> <artifactId>eclipse-collections</artifactId> <version>10.4.0</version> </dependency> </dependencies> import org.eclipse.collections.api.list.ImmutableList; import org.eclipse.collections.impl.factory.Lists; public class Main { public static void main(String[] args) { ImmutableList<Integer> numbers = Lists.immutable.of(1, 2, 3, 4, 5); double average = numbers System.out.println("Average: " + average); } }