package Java12; import java.util.Arrays; import java.util.List; import java.util.function.Function; import java.util.stream.Collectors; public class StreamExample { public static void main(String[] args) { //Collectors.teeing //Collectors.teeing() is a new collector added in Java 12. It is used to combine the result of two collectors into a single result. //The first argument is the first collector, the second argument is the second collector, and the third argument is a function that combines the results of the two collectors. //The function should not be null. //Collectors.teeing() is used to calculate the average of the list of integers. //The first collector calculates the sum of the list of integers. //The second collector calculates the count of the list of integers. //The third argument is a function that calculates the average of the sum and count. //The function takes two arguments, the sum and the count, and returns the average. List list = Arrays.asList(1, 2, 3, 4, 5); Double average = list.stream().collect( Collectors.teeing(Collectors.summingDouble(i -> i), Collectors.counting(), (sum, count) -> sum / count)); System.out.println("Average = " + average); } }