// other operations, the cache and the removal queue won't change from this point on.

    // Verify that each received removal notification was valid
    for (RemovalNotification<String, String> notification : removalListener) {
      assertEquals("Invalid removal notification", notification.getKey(), notification.getValue());
    }

    CacheStats stats = cache.stats();
    assertEquals(removalListener.size(), stats.evictionCount());

    // other operations, the cache and the removal queue won't change from this point on.

    // Verify that each received removal notification was valid
    for (RemovalNotification<String, String> notification : removalListener) {
      assertEquals("Invalid removal notification", notification.getKey(), notification.getValue());
    }

    CacheStats stats = cache.stats();
    assertEquals(removalListener.size(), stats.evictionCount());

      QueuingRemovalListener<K, V> listener, K key, V value, RemovalCause cause) {
    RemovalNotification<K, V> notification = listener.remove();
    assertSame(key, notification.getKey());
    assertSame(value, notification.getValue());
    assertSame(cause, notification.getCause());
  }

  // Segment core tests

  public void testNewEntry() {

  static class QueuingRemovalListener<K, V> extends ConcurrentLinkedQueue<RemovalNotification<K, V>>
      implements RemovalListener<K, V> {

    @Override
    public void onRemoval(RemovalNotification<K, V> notification) {
      add(notification);
    }
  }

  /**
   * {@link RemovalListener} that counts each {@link RemovalNotification} it receives, and provides
   * access to the most-recently received one.
   */

        // Assert
        assertEquals("Status of test-cluster is changed to RED.", result);
        // Note: Notification sending is tested but we don't verify the mock since it uses complex callback mechanism
    }

    // Test state change with empty notification addresses
    public void test_execute_stateChangeEmptyNotificationAddresses() {
        // Setup mock components

            return redirectToLogin();
        }
        validate(form, messages -> {}, () -> asHtml(virtualHost(path_IndexJsp)).renderWith(data -> {
            buildInitParams();
            RenderDataUtil.register(data, "notification", fessConfig.getNotificationSearchTop());
        }));
        if (!form.hasConditionQuery()) {
            if (StringUtil.isNotBlank(form.q)) {
                form.as.put("q", new String[] { form.q });

        // Should not throw exception when notification is disabled
        try {
            crawler.sendMail(infoMap);
        } catch (Exception e) {
            fail("Should not throw exception: " + e.getMessage());
        }
    }

    public void test_sendMail_withNotificationEnabled() {
        // Override fessConfig to enable notification

                logger.info("[CRAWL INFO] {}", buf);
            }

            // notification
            try {
                crawler.sendMail(infoMap);
            } catch (final Exception e) {
                logger.warn("Failed to send a mail.", e);
            }

        }
    }

    /**
     * Sends email notification with crawling results and statistics.

 *   <li>keys automatically wrapped in {@code WeakReference}
 *   <li>values automatically wrapped in {@code WeakReference} or {@code SoftReference}
 *   <li>notification of evicted (or otherwise removed) entries
 *   <li>accumulation of cache access statistics
 * </ul>
 *
 * <p>These features are all optional; caches can be created using all or none of them. By default,