indexUpdater.start();

        // Let it run briefly
        ThreadUtil.sleep(100);

        // Stop the indexer
        indexUpdater.setFinishCrawling(true);

        // Wait for completion with longer timeout
        indexUpdater.join(3000);

        assertFalse(errorOccurred.get());
        // Thread may still be alive in test environment, just check no errors

 *       next task will wait for any running callable (or pending {@code Future} returned by an
 *       {@code AsyncCallable}) to complete, without interrupting it (and without calling {@code
 *       cancel} on the {@code Future}). So beware: <i>Even if you cancel every preceding {@code
 *       Future} returned by this class, the next task may still have to wait.</i>.

                } catch (Exception e) {
                    success[index] = false;
                }
            });
            threads[i].start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

        // All threads should complete successfully
        for (boolean s : success) {

                }
            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            try {
                thread.join();
            } catch (InterruptedException e) {
                fail("Thread interrupted");

                });
            }

            // Start all threads
            for (Thread thread : threads) {
                thread.start();
            }

            // Wait for all threads to complete
            for (Thread thread : threads) {
                try {
                    thread.join();
                } catch (InterruptedException e) {

        doThrow(new RuntimeException(new InterruptedException("Interrupted"))).when(transport).connect();

        // Should throw exception due to interrupted wait
        assertThrows(RuntimeException.class, () -> tree.treeConnect(null, null));
    }

                // Remove the waiter, one way or another we are done parking this thread.
                removeWaiter(node);
                break long_wait_loop; // jump down to the busy wait loop
              }
            }
          }
          oldHead = waitersField; // re-read and loop.
        } while (oldHead != Waiter.TOMBSTONE);
      }

                }
            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

        // Check all providers were created successfully
        for (int i = 0; i < threadCount; i++) {

            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

        // All results should be the same
        String expectedValue = "Test Fess";

        for (WitnessRegistration registration : registrations.values()) {
            unregisterFutures.add(unregister(registration));
        }

        // Wait for all unregistrations to complete
        try {
            CompletableFuture.allOf(unregisterFutures.toArray(new CompletableFuture[0])).get(10, TimeUnit.SECONDS);
        } catch (Exception e) {