Hackforge Academy

Explanation

Stream is used to process collections in
functional style.

Code:

List<Integer> list = Arrays.asList(1,2,3);

Explanation

filter() is used to filter elements.

Code:

list.stream()
.filter(n -> n>1)
.forEach(System.out::println);

Explanation

map() transforms elements.

Code:

list.stream()
.map(n -> n*2)
.forEach(System.out::println);

Explanation

collect() gathers stream results into a
collection.

Code:

List<Integer> result = 
list.stream().collect(Collectors.toList());

Explanation

reduce() performs aggregation operations.

Code:

int sum = list.stream().reduce(0,(a,b)->a+b);