Streams on 1Stop

Java Streams

Mon, 29 Jul 2024 16:21:42 -0400

JAVA Streams

Sum of Elements

Given a list of integers, compute the sum of all numbers.

// using sum
List<Integer> arr = Arrays.asList(1, 4, 5, 6, 22, 3, 90, 89, 2, 1, 3, 4, 55, 6);

int sum = arr.stream()
 .mapToInt(Integer::intValue)
 .sum();
// or
int sum3 = arr.stream()
 .reduce((a,b) -> a + b)
 .get();

// or
int sum2 = arr.stream()
 .reduce(0,
 (total, n) -> total + n,
 (total1, total2) -> total1 + total2);

Average of Elements

Given a list of integers, compute the average of all numbers.