valueEquivalence == null, "value equivalence was already set to %s", valueEquivalence);
    this.valueEquivalence = checkNotNull(equivalence);
    return this;
  }

  Equivalence<Object> getValueEquivalence() {
    return MoreObjects.firstNonNull(valueEquivalence, getValueStrength().defaultEquivalence());
  }

  /**
   * Sets the minimum total size for the internal hash tables. For example, if the initial capacity