* loaded) value, or null. Multiple concurrent calls to {@link Cache} lookup methods on an absent
   * value can result in multiple misses, all returning the results of a single cache load
   * operation.
   */
  public long missCount() {
    return missCount;
  }

  /**
   * Returns the ratio of cache requests which were misses. This is defined as {@code missCount /

   * loaded) value, or null. Multiple concurrent calls to {@link Cache} lookup methods on an absent
   * value can result in multiple misses, all returning the results of a single cache load
   * operation.
   */
  public long missCount() {
    return missCount;
  }

  /**
   * Returns the ratio of cache requests which were misses. This is defined as {@code missCount /

  public Stats yStats() {
    return yStats;
  }

  /**
   * Returns the population covariance of the values. The count must be non-zero.
   *
   * <p>This is guaranteed to return zero if the dataset contains a single pair of finite values. It
   * is not guaranteed to return zero when the dataset consists of the same pair of values multiple
   * times, due to numerical errors.
   *
   * <h3>Non-finite values</h3>
   *

   */
  private static final SuccessorsFunction<Character> TWO_TREES = createDirectedGraph("ab", "cd");

  /**
   * A graph consisting of a single root {@code a}:
   *
   * <pre>{@code
   * a
   * }</pre>
   */
  private static final SuccessorsFunction<Character> SINGLE_ROOT = createSingleRootGraph();

  /**
   * A graph that is not a tree (for example, it has two antiparallel edge between {@code e} and

   * All node connections in this graph, in edge insertion order.
   *
   * <p>Note: This field and {@link #adjacentNodeValues} cannot be combined into a single
   * LinkedHashMap because one target node may be mapped to both a predecessor and a successor. A
   * LinkedHashMap combines two such edges into a single node-value pair, even though the edges may
   * not have been inserted consecutively.
   */

    assertThat(removalListener.getCount()).isEqualTo(2);

    // Should we pepper more of these calls throughout the above? Where?
    CacheTesting.checkValidState(cache);
  }

  /**
   * Tests that when a single entry exceeds the segment's max weight, the new entry is immediately
   * evicted and nothing else.
   */
  public void testEviction_maxWeight_entryTooBig() {

   * The table size is doubled upon further contention until
   * reaching the nearest power of two greater than or equal to the
   * number of CPUS. Table slots remain empty (null) until they are
   * needed.
   *
   * A single spinlock ("busy") is used for initializing and
   * resizing the table, as well as populating slots with new Cells.
   * There is no need for a blocking lock; when the lock is not

          assertFalse(desc, isGuarded(method));
        } else {
          assertTrue(desc, isGuarded(method));
        }
        // we can't make an assumption about isTimed() because now we have single-parameter methods
        // that accept a java.time.Duration
        assertFalse(desc, isLongTimeUnitBased(method));
        break;
      case 2:
        if (isDurationBased(method)) {

    }

    // wait for entries to expire, but don't call expireEntries
    ticker.advance(EXPIRING_TIME * 10, MILLISECONDS);

    // add a single unexpired entry
    cache.getUnchecked(KEY_PREFIX + 11);

    // collections views shouldn't expose expired entries
    assertEquals(1, Iterators.size(cache.asMap().entrySet().iterator()));

   * @return a {@code CharSource} containing the concatenated data
   * @since 15.0
   */
  public static CharSource concat(Iterable<? extends CharSource> sources) {
    return new ConcatenatedCharSource(sources);
  }

  /**
   * Concatenates multiple {@link CharSource} instances into a single source. Streams returned from