return (totalLoadCount == 0) ? 0.0 : (double) totalLoadTime / totalLoadCount;
  }

  /**
   * Returns the number of times an entry has been evicted. This count does not include manual
   * {@linkplain Cache#invalidate invalidations}.
   */
  public long evictionCount() {
    return evictionCount;
  }

  /**
   * Returns a new {@code CacheStats} representing the difference between this {@code CacheStats}

              return nameComparison;
            } else {
              return Ints.compare(m1.getParameterTypes().length, m2.getParameterTypes().length);
            }
          }
        });
  }

  /** Validates that the given method's signature meets all of our assumptions. */
  private static void validateMethod(Method method) {
    String desc = method.toString();

    assertTrue(desc, isAnyEnter(method) || isWaitFor(method));

    Set<E> delegate = delegateOrNull();
    if (delegate != null) {
      metadata =
          Ints.constrainToRange(size(), CompactHashing.DEFAULT_SIZE, CompactHashing.MAX_SIZE);
      delegate.clear(); // invalidate any iterators left over!
      table = null;
      size = 0;
    } else {
      Arrays.fill(requireElements(), 0, size, null);
      CompactHashing.tableClear(requireTable());

  }

  @Override
  public void invalidate(Object key) {
    throw new UnsupportedOperationException();
  }

  /** @since 11.0 */
  @Override
  // For discussion of <? extends Object>, see getAllPresent.
  public void invalidateAll(Iterable<? extends Object> keys) {
    for (Object key : keys) {
      invalidate(key);
    }
  }

  @Override
  public void invalidateAll() {

  }

  public void testApply() {
    when(mock.apply("key")).thenReturn(Boolean.TRUE);
    assertSame(Boolean.TRUE, forward.apply("key"));
  }

  public void testInvalidate() {
    forward.invalidate("key");
    verify(mock).invalidate("key");
  }

  public void testRefresh() throws ExecutionException {
    forward.refresh("key");
    verify(mock).refresh("key");
  }

  public void testInvalidateAll() {

  /** Magic value indicating the absence of a port number. */
  private static final int NO_PORT = -1;

  /** Hostname, IPv4/IPv6 literal, or unvalidated nonsense. */
  private final String host;

  /** Validated port number in the range [0..65535], or NO_PORT */
  private final int port;

  /** True if the parsed host has colons, but no surrounding brackets. */
  private final boolean hasBracketlessColons;

  }


  public void testInvalidate_empty() {
    for (LoadingCache<Object, Object> cache : caches()) {
      cache.getUnchecked("a");
      cache.getUnchecked("b");
      cache.invalidate("a");
      cache.invalidate("b");
      cache.invalidate(0);
      checkEmpty(cache);
    }
  }

  public void testInvalidateAll_empty() {
    for (LoadingCache<Object, Object> cache : caches()) {
      cache.getUnchecked("a");

   *   <li>{@code safeMax == Character.MAX_VALUE}
   *   <li>{@code unsafeReplacement == null}
   * </ul>
   *
   * <p>For performance reasons escapers created by this builder are not Unicode aware and will not
   * validate the well-formedness of their input.
   */
  public static Builder builder() {
    return new Builder();
  }

  /**
   * A builder for simple, fast escapers.
   *

    cache.put(0, 10);

    assertEquals(Integer.valueOf(10), cache.get(0, loader));
    assertEquals(Integer.valueOf(1), cache.get(20, loader));
    assertEquals(Integer.valueOf(2), cache.get(34, loader));

    cache.invalidate(0);
    assertEquals(Integer.valueOf(3), cache.get(0, loader));

    cache.put(0, 10);
    cache.invalidateAll();
    assertEquals(Integer.valueOf(4), cache.get(0, loader));
  }

        new Receiver<ReferenceEntry<Integer, Integer>>() {
          @Override
          public void accept(ReferenceEntry<Integer, Integer> entry) {
            Integer key = entry.getKey();
            cache.invalidate(key);
          }
        });
  }

  public void testEviction_lru() {
    // test lru within a single segment
    IdentityLoader<Integer> loader = identityLoader();