@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() {

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

  @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() {

      spec.keyStrength = strength;
    }
  }

  /** Parse weakValues and softValues */
  private static final class ValueStrengthParser implements ValueParser {
    private final Strength strength;

    ValueStrengthParser(Strength strength) {
      this.strength = strength;
    }

    @Override

      spec.keyStrength = strength;
    }
  }

  /** Parse weakValues and softValues */
  private static final class ValueStrengthParser implements ValueParser {
    private final Strength strength;

    ValueStrengthParser(Strength strength) {
      this.strength = strength;
    }

    @Override

   * @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);

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

        }
      };

  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(

// advanced techniques like specifying lock strength and optimizer hints. See the
// [docs] for more depth.
//
//	// add a simple limit clause
//	db.Clauses(clause.Limit{Limit: 1}).Find(&User{})
//	// tell the optimizer to use the `idx_user_name` index
//	db.Clauses(hints.UseIndex("idx_user_name")).Find(&User{})
//	// specify the lock strength to UPDATE
//	db.Clauses(clause.Locking{Strength: "UPDATE"}).Find(&users)
//

    checkStrength(map, Strength.WEAK, Strength.STRONG);
    assertThat(map.entryHelper)
        .isInstanceOf(MapMakerInternalMap.WeakKeyStrongValueEntry.Helper.class);
  }

  public void testSetWeakValues() {
    MapMakerInternalMap<Object, Object, ?, ?> map = makeMap(createMapMaker().weakValues());
    checkStrength(map, Strength.STRONG, Strength.WEAK);
    assertThat(map.entryHelper)