[Java] Executors 로 간단 multithread 테스트

이전 글의 참고 문서들을 먼저 보시면 좋습니다.

http://jjeong.tistory.com/1296

package hello.executors;

import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;

public class HelloExecutors {

  public static class HelloCallableThread implements Callable<Integer> {
    int input;

    public HelloCallableThread(int input) {
      this.input = input;
    }

    @Override
    public Integer call() throws Exception {
      return input + 1;
    }
  }

  public static void main(String[] args) throws Exception {
    ExecutorService executorService = Executors.newFixedThreadPool(4);
    Set<Callable<Integer>> callables = new HashSet<Callable<Integer>>();

    callables.add(new HelloCallableThread(1));
    callables.add(new HelloCallableThread(2));
    callables.add(new HelloCallableThread(3));
    callables.add(new HelloCallableThread(4));

    List<Future<Integer>> futures = executorService.invokeAll(callables);

    for(Future<Integer> future : futures){
      System.out.println("future.get = " + future.get());
    }

    executorService.shutdown();
    executorService.awaitTermination(1, TimeUnit.SECONDS);
  }
}