How to sum even numbers with Reduce in java
In this Java code snippet, a list of integers named `numbers` is created with values 2, 4, 6, 8, and 10. Using Java 8 streams, the code calculates the sum of even numbers from the `numbers` list.
The `filter` operation selects only even integers by checking the remainder of division by 2. The `reduce` operation then adds these even numbers together, starting with an initial value of 0, using the `Integer::sum` method reference.
The result stored in `sumOfEvens` is the sum of the even integers in the list.
List<Integer> numbers = Arrays.asList(2, 4, 6, 8, 10); int sumOfEvens = numbers.stream() .filter(n -> n % 2 == 0) .reduce(0, Integer::sum);