*
 * <p>Most implementations will only need to implement {@link #load}. Other methods may be
 * overridden as desired.
 *
 * <p>Usage example:
 *
 * {@snippet :
 * CacheLoader<Key, Graph> loader = new CacheLoader<Key, Graph>() {
 *   public Graph load(Key key) throws AnyException {
 *     return createExpensiveGraph(key);
 *   }
 * };

   * that tests equivalence using their lengths:
   *
   * {@snippet :
   * equiv.wrap("a").equals(equiv.wrap("b")) // true
   * equiv.wrap("a").equals(equiv.wrap("hello")) // false
   * }
   *
   * <p>Note in particular that an equivalence wrapper is never equal to the object it wraps.
   *
   * {@snippet :
   * equiv.wrap(obj).equals(obj) // always false
   * }
   *
   * @since 10.0

   * and not contents.
   *
   * <p>This is useful for implementing {@link Object#hashCode()}. For example, in an object that
   * has three properties, {@code x}, {@code y}, and {@code z}, one could write:
   *
   * {@snippet :
   * public int hashCode() {
   *   return Objects.hashCode(getX(), getY(), getZ());
   * }
   * }
   *
   * <p><b>Warning:</b> When a single object is supplied, the returned hash code does not equal the

 * generally prefer the methods in {@link Comparator}; see <a href="#java8">below</a>.
 *
 * <p>Example usage of {@code ComparisonChain}:
 *
 * {@snippet :
 * public int compareTo(Foo that) {
 *   return ComparisonChain.start()
 *       .compare(this.aString, that.aString)
 *       .compare(this.anInt, that.anInt)

   */
  @Override
  boolean equals(@Nullable Object object);

  /**
   * Returns the hash code for this instance. This is defined as the hash code of
   *
   * {@snippet :
   * Arrays.asList(entriesOnlyOnLeft(), entriesOnlyOnRight(),
   *     entriesInCommon(), entriesDiffering())
   * }
   */
  @Override
  int hashCode();

  /**

   */
  @Override
  boolean equals(@Nullable Object object);

  /**
   * Returns the hash code for this instance. This is defined as the hash code of
   *
   * {@snippet :
   * Arrays.asList(entriesOnlyOnLeft(), entriesOnlyOnRight(),
   *     entriesInCommon(), entriesDiffering())
   * }
   */
  @Override
  int hashCode();

  /**

 * recursion by calling {@link #visit} for any {@code Type} while visitation is in progress. For
 * example, this can be used to reject wildcards or type variables contained in a type as in:
 *
 * {@snippet :
 * new TypeVisitor() {
 *   protected void visitParameterizedType(ParameterizedType t) {
 *     visit(t.getOwnerType());
 *     visit(t.getActualTypeArguments());
 *   }

   * {@code Comparator}) input elements, in ascending order, as an unmodifiable {@code List}. Ties
   * are broken arbitrarily.
   *
   * <p>For example:
   *
   * {@snippet :
   * Stream.of("foo", "quux", "banana", "elephant")
   *     .collect(least(2, comparingInt(String::length)))
   * // returns {"foo", "quux"}
   * }
   *

     * <p>Returns {@code true} if the given object is also a multiset entry and the two entries
     * represent the same element and count. That is, two entries {@code a} and {@code b} are equal
     * if:
     *
     * {@snippet :
     * Objects.equals(a.getElement(), b.getElement())
     *     && a.getCount() == b.getCount()
     * }
     */
    @Override
    // TODO(kevinb): check this wrt TreeMultiset?

 * contains objects that are supposed to be equal to each other. Objects of different groups are
 * expected to be unequal. For example:
 *
 * {@snippet :
 * EquivalenceTester.of(someStringEquivalence)
 *     .addEquivalenceGroup("hello", "h" + "ello")
 *     .addEquivalenceGroup("world", "wor" + "ld")
 *     .test();
 * }
 *