This example will show how to convert a Stream into a Hashset using Java 8. A Collector is a reduction operation that will accumulate elements from a stream into a cumulative result. We must supply a Collector in order to gather all the Stream’s items in a Set which we can do by using a connivence method toSet() from the Collectors utility class.
@Test
public void stream_to_set() {
Set<Integer> numbers = Stream.of(1, 2, 3)
.collect(Collectors.toSet());
assertTrue(numbers.size() == 3);
}If you prefer, you could use a static import.
...
import static java.util.stream.Collectors.toSet;
...
@Test
public void stream_to_set() {
Set<Integer> numbers = Stream.of(1, 2, 3)
.collect(toSet());
assertTrue(numbers.size() == 3);
}