StreamTest.java

import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import java.util.stream.Stream;

public class StreamTest {

  private static int MAX_ITERATION = 3_000;

  public static void main(String[] args) {
    List<String> list = new LinkedList<>();
    for (int i = 0; i < MAX_ITERATION; i++) {
      list.add(String.valueOf(i));
    }
    long start = 0, end = 0;

    long sum[] = {0};
    start = System.currentTimeMillis();
    Stream<String> streamToParallel = list.stream().parallel();
    streamToParallel.forEach(value -> {
      long s = System.currentTimeMillis();
      print(value);
      long e = System.currentTimeMillis() - s;
      //System.out.println(e);
      sum[0] = sum[0] + e;
      System.out.println(sum[0]);
    });
    end = System.currentTimeMillis();
    System.out.println("병렬처리: " + (end - start)); //병렬처리: 4282

  }

  public static void print(String str) {
    System.out.println(str+ " : "+Thread.currentThread().getName());
    try {
      Thread.sleep(10);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }
  }

}