Java 8 Convert Streams to & from Lists Examples
Converting from Streams to Lists
Converting a Stream to a List is extremely simple since we can use the
stream’s collect() function with the Collectors.toList() built-in function
like in the example below:
package xyz.byexample.java8;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
public class StreamToList {
public static void main(String[] args) {
Stream<Integer> numbersStream = Stream.of(1, 2, 3, 4, 5);
List<Integer> numbersList = numbersStream.collect(Collectors.toList());
numbersList.forEach(number -> System.out.println(number));
}
}
Output
1
2
3
4
5
Converting from Lists to Streams
Again, converting a List to a Stream is extremely simple thanks to the
built-in functions stream() and parallelStream() on the List type.
List<String> lettersList = Arrays.asList("a", "b", "c", "d", "e");
Stream<String> lettersStream = lettersList.stream();
Stream<String> lettersParallelStream = lettersList.parallelStream();