@Test
public void testManagedMultiPreregisteredExecutionCallbackCompletableFuture() throws Exception {
HazelcastInstanceProxy proxy = (HazelcastInstanceProxy) createHazelcastInstance();
Field originalField = HazelcastInstanceProxy.class.getDeclaredField("original");
originalField.setAccessible(true);
HazelcastInstanceImpl hz = (HazelcastInstanceImpl) originalField.get(proxy);
NodeEngine nodeEngine = hz.node.nodeEngine;
ExecutionService es = nodeEngine.getExecutionService();
final CountDownLatch latch1 = new CountDownLatch(1);
final CountDownLatch latch2 = new CountDownLatch(2);