@CanIgnoreReturnValue
  MapMaker setValueStrength(Strength strength) {
    checkState(valueStrength == null, "Value strength was already set to %s", valueStrength);
    valueStrength = checkNotNull(strength);
    if (strength != Strength.STRONG) {
      // STRONG could be used during deserialization.
      useCustomMap = true;
    }
    return this;
  }

  Strength getValueStrength() {

        }
      };

  private CacheBuilderFactory factoryWithAllKeyStrengths() {
    return new CacheBuilderFactory()
        .withKeyStrengths(ImmutableSet.of(STRONG, Strength.WEAK))
        .withValueStrengths(ImmutableSet.of(STRONG, Strength.WEAK, Strength.SOFT));
  }

  private Iterable<LoadingCache<Key, String>> caches() {
    CacheBuilderFactory factory = factoryWithAllKeyStrengths();
    return Iterables.transform(

  private Set<DurationSpec> refreshes = Sets.newHashSet((DurationSpec) null);
  private Set<Strength> keyStrengths = Sets.newHashSet((Strength) null);
  private Set<Strength> valueStrengths = Sets.newHashSet((Strength) null);

  @CanIgnoreReturnValue
  CacheBuilderFactory withConcurrencyLevels(Set<Integer> concurrencyLevels) {

      MapMaker builder) {
    if (builder.getKeyStrength() == Strength.STRONG
        && builder.getValueStrength() == Strength.STRONG) {
      return new MapMakerInternalMap<>(builder, StrongKeyStrongValueEntry.Helper.<K, V>instance());
    }
    if (builder.getKeyStrength() == Strength.STRONG
        && builder.getValueStrength() == Strength.WEAK) {

   * @throws IllegalStateException if the key strength was already set
   */
  @GwtIncompatible // java.lang.ref.WeakReference
  @CanIgnoreReturnValue
  public CacheBuilder<K, V> weakKeys() {
    return setKeyStrength(Strength.WEAK);
  }

  @CanIgnoreReturnValue
  CacheBuilder<K, V> setKeyStrength(Strength strength) {
    checkState(keyStrength == null, "Key strength was already set to %s", keyStrength);

    checkStrength(map, Strength.WEAK, Strength.STRONG);
    assertSame(EntryFactory.WEAK, map.entryFactory);
  }

  public void testSetWeakValues() {
    LocalCache<Object, Object> map = makeLocalCache(createCacheBuilder().weakValues());
    checkStrength(map, Strength.STRONG, Strength.WEAK);
    assertSame(EntryFactory.STRONG, map.entryFactory);
  }

      }
      statsCounter.recordEviction();
      return removal;
    }
  }

  /**
   * Any updates to LocalCache.Strength used in CacheBuilder need to be matched in this class for
   * compilation purposes.
   */
  enum Strength {
    /*
     * TODO(kevinb): If we strongly reference the value and aren't loading, we needn't wrap the
     * value. This could save ~8 bytes per entry.
     */

            if (arg != null) {
                buf.append(arg.getClass().getName());
            } else {
                buf.append("null");
            }
            buf.append(", ");
        }
        buf.setLength(buf.length() - 2);
        return new String(buf);
    }

    private static String getSignature(final Class<?>... paramTypes) {
        if (paramTypes == null || paramTypes.length == 0) {
            return "";

        }
        Throwable t = cause.getCause();
        while (t != null) {
            buf.append(t.getMessage()).append("], [");
            t = t.getCause();
        }
        buf.setLength(buf.length() - 4);
        return new String(buf);
    }

        if (argTypes != null && argTypes.length > 0) {
            for (final Class<?> argType : argTypes) {
                buf.append(argType.getName()).append(", ");
            }
            buf.setLength(buf.length() - 2);
        }
        buf.append(")");
        return new String(buf);
    }

    /**
     * Returns the string representation of the method signature.
     *
     * @param methodName