Guava - 병렬 프로그래밍 Futures 상세 정보

Futures.addCallback(ListenableFuture, new FutureCallback<Object>() {

  public void onSuccess(Object result) {
    System.out.printf("onSuccess with: %s%n", result);
  }

  public void onFailure(Throwable thrown) {
    System.out.printf("onFailure %s%n", thrown.getMessage());
  }
});

@Test
public void should_test_furture() throws Exception {
  ListeningExecutorService service = MoreExecutors.listeningDecorator(Executors.newFixedThreadPool(10));

  ListenableFuture future1 = service.submit(new Callable<Integer>() {
    public Integer call() throws InterruptedException {
      Thread.sleep(1000);
      System.out.println("call future 1.");
      return 1;
    }
  });

  ListenableFuture future2 = service.submit(new Callable<Integer>() {
    public Integer call() throws InterruptedException {
      Thread.sleep(1000);
      System.out.println("call future 2.");
  //    throw new RuntimeException("----call future 2.");
      return 2;
    }
  });

  final ListenableFuture allFutures = Futures.allAsList(future1, future2);

  final ListenableFuture transform = Futures.transform(allFutures, new AsyncFunction<List<Integer>, Boolean>() {
    @Override
    public ListenableFuture apply(List<Integer> results) throws Exception {
      return Futures.immediateFuture(String.format("success future:%d", results.size()));
    }
  });

  Futures.addCallback(transform, new FutureCallback<Object>() {

    public void onSuccess(Object result) {
      System.out.println(result.getClass());
      System.out.printf("success with: %s%n", result);
    }

    public void onFailure(Throwable thrown) {
      System.out.printf("onFailure%s%n", thrown.getMessage());
    }
  });

  System.out.println(transform.get());
}