FileSystemTest.java

@Test
  @Repeat(times=1000)
  public void testAsyncFileConcurrency() throws Exception {
    String fileName = "some-file.dat";

    AtomicReference<AsyncFile> arFile = new AtomicReference<>();
    CountDownLatch latch = new CountDownLatch(1);
    vertx.fileSystem().open(testDir + pathSep + fileName, new OpenOptions(), ar -> {
      if (ar.succeeded()) {
        AsyncFile af = ar.result();
        arFile.set(af);
      } else {
        fail(ar.cause().getMessage());
      }
      latch.countDown();
    });
    awaitLatch(latch);

    AsyncFile af = arFile.get();

    Buffer buff = Buffer.buffer(randomByteArray(4096));
    for (int i = 0; i < 100000; i++) {
      af.write(buff);
    }

    af.close(onSuccess(v -> {
      testComplete();
    }));

    await();
  }