* {@link #rightValue} are not equal, and one but not both of them may be null.
   *
   * @since 2.0
   */
  @DoNotMock("Use Maps.difference")
  interface ValueDifference<V extends @Nullable Object> {
    /** Returns the value from the left map (possibly null). */
    @ParametricNullness
    V leftValue();

   * {@link #rightValue} are not equal, and one but not both of them may be null.
   *
   * @since 2.0
   */
  @DoNotMock("Use Maps.difference")
  interface ValueDifference<V extends @Nullable Object> {
    /** Returns the value from the left map (possibly null). */
    @ParametricNullness
    V leftValue();

        if (valueEquivalence.equivalent(leftValue, rightValue)) {
          onBoth.put(leftKey, leftValue);
        } else {
          differences.put(leftKey, ValueDifferenceImpl.create(leftValue, rightValue));
        }
      } else {
        onlyOnLeft.put(leftKey, leftValue);
      }
    }
  }

        if (valueEquivalence.equivalent(leftValue, rightValue)) {
          onBoth.put(leftKey, leftValue);
        } else {
          differences.put(leftKey, ValueDifferenceImpl.create(leftValue, rightValue));
        }
      } else {
        onlyOnLeft.put(leftKey, leftValue);
      }
    }
  }