Stream reduce(U identity, BiFunction accumulator, BinaryOperator combiner) example
Description
Stream reduce(U identity, BiFunction<U,? super T,U> accumulator,
BinaryOperator<U> combiner) performs a reduction on
the elements of this stream, using the provided identity, accumulation and combining functions.
Syntax
reduce has the following syntax.
<U> U reduce(U identity, BiFunction<U,? super T,U> accumulator, BinaryOperator<U> combiner)
Example
The following example shows how to use reduce.
import java.util.Arrays;
import java.util.List;
/*from w ww . j a v a 2 s. c om*/
public class Main {
public static void main(String[] args) {
List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5);
double sum = numbers
.parallelStream()
.reduce(0.0, (partialSum, a) -> partialSum + a, Double::sum);
System.out.println(sum);
}
}
The code above generates the following result.
