}
    return hash;
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (obj instanceof PairwiseEquivalence) {
      @SuppressWarnings("unchecked")
      PairwiseEquivalence<Object, Object> that = (PairwiseEquivalence<Object, Object>) obj;
      return this.elementEquivalence.equals(that.elementEquivalence);
    }

    return false;
  }

  @Override

    }
    return hash;
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (obj instanceof PairwiseEquivalence) {
      @SuppressWarnings("unchecked")
      PairwiseEquivalence<Object, Object> that = (PairwiseEquivalence<Object, Object>) obj;
      return this.elementEquivalence.equals(that.elementEquivalence);
    }

    return false;
  }

  @Override