/**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testPrepareQueue() throws Exception {
    // Random sequence names.
    String queueName1 = UUID.randomUUID().toString();
    String queueName2 = UUID.randomUUID().toString();

    CollectionConfiguration colCfg = config(false);

    IgniteQueue queue1 = grid(0).queue(queueName1, 0, colCfg);
    IgniteQueue queue2 = grid(0).queue(queueName2, 0, colCfg);
    IgniteQueue queue3 = grid(0).queue(queueName1, 0, colCfg);

    assertNotNull(queue1);
    assertNotNull(queue2);
    assertNotNull(queue3);
    assert queue1.equals(queue3);
    assert queue3.equals(queue1);
    assert !queue3.equals(queue2);

    queue1.close();
    queue2.close();
    queue3.close();

    assertNull(grid(0).queue(queueName1, 0, null));
    assertNull(grid(0).queue(queueName2, 0, null));
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testAddUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    String val = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    assert queue.add(val);

    assert val.equals(queue.poll());
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testAddDeleteUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    String val = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    assert queue.add(val);

    assert queue.remove(val);

    assert queue.isEmpty();
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testPutGetMultithreadUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    final IgniteQueue<String> queue = grid(0).queue(queueName, QUEUE_CAPACITY, config(false));

    multithreaded(
        new Callable<Void>() {
          @Override
          public Void call() throws Exception {
            String thName = Thread.currentThread().getName();

            for (int i = 0; i < 5; i++) {
              queue.put(thName);
              queue.peek();
              queue.take();
            }

            return null;
          }
        },
        THREAD_NUM);

    assert queue.isEmpty() : queue.size();
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testPutRemoveMultiThreadedUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    final IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    multithreaded(
        new Callable<String>() {
          @Override
          public String call() throws Exception {
            String thread = Thread.currentThread().getName();

            for (int i = 0; i < QUEUE_CAPACITY; i++) queue.put(thread);

            info("Finished loop 1: " + thread);

            queue.clear();

            info("Cleared queue 1: " + thread);

            return "";
          }
        },
        THREAD_NUM);

    assert queue.isEmpty() : "Queue must be empty. " + queue.size();
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testIterator() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    for (int i = 0; i < 100; i++) assert queue.add(Integer.toString(i));

    Iterator<String> iter1 = queue.iterator();

    int cnt = 0;
    for (int i = 0; i < 100; i++) {
      assertNotNull(iter1.next());
      cnt++;
    }

    assertEquals(100, queue.size());
    assertEquals(100, cnt);

    assertNotNull(queue.take());
    assertNotNull(queue.take());
    assertTrue(queue.remove("33"));
    assertTrue(queue.remove("77"));

    assertEquals(96, queue.size());

    Iterator<String> iter2 = queue.iterator();

    try {
      iter2.remove();
    } catch (IllegalStateException e) {
      info("Caught expected exception: " + e);
    }

    iter2.next();
    iter2.remove();

    cnt = 0;
    while (iter2.hasNext()) {
      assertNotNull(iter2.next());
      cnt++;
    }

    assertEquals(95, cnt);
    assertEquals(95, queue.size());

    iter2.remove();
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testPutGetUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, QUEUE_CAPACITY, config(false));

    String thName = Thread.currentThread().getName();

    for (int i = 0; i < 5; i++) {
      queue.put(thName);
      queue.peek();
      queue.take();
    }

    assert queue.isEmpty() : queue.size();
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testAddPollUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    assert queue.add("1");

    assert queue.add("2");

    assert queue.add("3");

    assertEquals("1", queue.poll());
    assertEquals("2", queue.poll());
    assertEquals("3", queue.poll());
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testPutRemoveUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    String thread = Thread.currentThread().getName();

    for (int i = 0; i < QUEUE_CAPACITY; i++) queue.put(thread);

    info("Finished loop 1: " + thread);

    queue.clear();

    info("Cleared queue 1: " + thread);

    assert queue.isEmpty() : "Queue must be empty. " + queue.size();
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testAddPeekUnbounded() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    IgniteQueue<String> queue = grid(0).queue(queueName, 0, config(false));

    String item1 = "1";
    assert queue.add(item1);

    String item2 = "2";
    assert queue.add(item2);

    String item3 = "3";
    assert queue.add(item3);

    assert item1.equals(queue.peek());
    assert item1.equals(queue.peek());
    assert !item2.equals(queue.peek());
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testQueueRemoveMultithreadBounded() throws Exception {
    // Random queue name.
    final String queueName = UUID.randomUUID().toString();

    final IgniteQueue<String> queue = grid(0).queue(queueName, QUEUE_CAPACITY, config(false));

    final CountDownLatch putLatch = new CountDownLatch(THREAD_NUM);

    final CountDownLatch clearLatch = new CountDownLatch(THREAD_NUM);

    for (int t = 0; t < THREAD_NUM; t++) {
      Thread th =
          new Thread(
              new Runnable() {
                @Override
                public void run() {
                  if (log.isDebugEnabled())
                    log.debug("Thread has been started." + Thread.currentThread().getName());

                  try {
                    // Thread must be blocked on put operation.
                    for (int i = 0; i < (QUEUE_CAPACITY * THREAD_NUM); i++)
                      queue.offer("anything", 3, TimeUnit.MINUTES);

                    fail("Queue failed");
                  } catch (IgniteException | IllegalStateException e) {
                    putLatch.countDown();

                    assert e.getMessage().contains("removed");

                    assert queue.removed();
                  }

                  if (log.isDebugEnabled())
                    log.debug("Thread has been stopped." + Thread.currentThread().getName());
                }
              });
      th.start();
    }

    for (int t = 0; t < THREAD_NUM; t++) {
      Thread th =
          new Thread(
              new Runnable() {
                @Override
                public void run() {
                  try {
                    IgniteQueue<String> queue = grid(0).queue(queueName, 0, null);

                    if (queue != null) queue.close();
                  } catch (Exception e) {
                    fail("Unexpected exception: " + e);
                  } finally {
                    clearLatch.countDown();
                  }
                }
              });
      th.start();
    }

    assert putLatch.await(3, TimeUnit.MINUTES);

    assert clearLatch.await(3, TimeUnit.MINUTES);

    try {
      assert queue.isEmpty() : queue.size();

      fail("Queue must be removed.");
    } catch (IgniteException | IllegalStateException e) {
      assert e.getMessage().contains("removed");

      assert queue.removed();
    }
  }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  public void testCollectionMethods() throws Exception {
    // Random queue name.
    String queueName = UUID.randomUUID().toString();

    IgniteQueue<SameHashItem> queue = grid(0).queue(queueName, 0, config(false));

    int retries = 100;

    // Initialize queue.
    for (int i = 0; i < retries; i++)
      queue.addAll(
          Arrays.asList(
              new SameHashItem(Integer.toString(i)), new SameHashItem(Integer.toString(i))));

    // Get arrays from queue.
    assertEquals(retries * 2, queue.toArray().length);

    SameHashItem[] arr2 = new SameHashItem[retries * 3];

    Object[] arr3 = queue.toArray(arr2);

    assertEquals(arr2, arr3);
    assertEquals(arr3[0], new SameHashItem("0"));

    // Check queue items.
    assertEquals(retries * 2, queue.size());

    assertTrue(queue.contains(new SameHashItem(Integer.toString(14))));

    assertFalse(queue.contains(new SameHashItem(Integer.toString(144))));

    Collection<SameHashItem> col1 =
        Arrays.asList(
            new SameHashItem(Integer.toString(14)),
            new SameHashItem(Integer.toString(14)),
            new SameHashItem(Integer.toString(18)));

    assertTrue(queue.containsAll(col1));

    Collection<SameHashItem> col2 =
        Arrays.asList(
            new SameHashItem(Integer.toString(245)),
            new SameHashItem(Integer.toString(14)),
            new SameHashItem(Integer.toString(18)));

    assertFalse(queue.containsAll(col2));

    // Try to remove item.
    assertTrue(queue.remove(new SameHashItem(Integer.toString(14))));

    assertEquals((retries * 2) - 1, queue.size());

    assertTrue(queue.contains(new SameHashItem(Integer.toString(14))));

    assertTrue(queue.remove(new SameHashItem(Integer.toString(14))));

    assertEquals((retries - 1) * 2, queue.size());

    assertFalse(queue.remove(new SameHashItem(Integer.toString(14))));

    // Try to remove some items.
    assertTrue(queue.contains(new SameHashItem(Integer.toString(33))));

    assertTrue(
        queue.removeAll(
            Arrays.asList(
                new SameHashItem(Integer.toString(15)),
                new SameHashItem(Integer.toString(14)),
                new SameHashItem(Integer.toString(33)),
                new SameHashItem(Integer.toString(1)))));

    assertFalse(queue.contains(new SameHashItem(Integer.toString(33))));

    // Try to retain all items.
    assertTrue(
        queue.retainAll(
            Arrays.asList(
                new SameHashItem(Integer.toString(15)),
                new SameHashItem(Integer.toString(14)),
                new SameHashItem(Integer.toString(33)),
                new SameHashItem(Integer.toString(1)))));

    assertFalse(queue.contains(new SameHashItem(Integer.toString(2))));

    assert queue.isEmpty();
  }