@Immutable
public interface HashFunction {
  /**
   * Begins a new hash code computation by returning an initialized, stateful {@code Hasher}
   * instance that is ready to receive data. Example:
   *
   * {@snippet :
   * HashFunction hf = Hashing.md5();
   * HashCode hc = hf.newHasher()
   *     .putLong(id)
   *     .putBoolean(isActive)
   *     .hash();
   * }
   */
  Hasher newHasher();

  /**

  }

  /**
   * Creates an instance of {@link ToStringHelper}.
   *
   * <p>This is helpful for implementing {@link Object#toString()}. Specification by example:
   *
   * {@snippet :
   * // Returns "ClassName{}"
   * MoreObjects.toStringHelper(this)
   *     .toString();
   *
   * // Returns "ClassName{x=1}"
   * MoreObjects.toStringHelper(this)
   *     .add("x", 1)
   *     .toString();

   * corresponding to smaller values of {@link Enum#ordinal()} should only be acquired before locks
   * with larger ordinals. Example:
   *
   * {@snippet :
   * enum MyLockOrder {
   *   FIRST, SECOND, THIRD;
   * }
   *
   * CycleDetectingLockFactory.WithExplicitOrdering<MyLockOrder> factory =

        checkNotNull(value, "value"));
  }

  /**
   * A builder for creating immutable table instances, especially {@code public static final} tables
   * ("constant tables"). Example:
   *
   * {@snippet :
   * static final ImmutableTable<Integer, Character, String> SPREADSHEET =
   *     new ImmutableTable.Builder<Integer, Character, String>()
   *         .put(1, 'A', "foo")
   *         .put(1, 'B', "bar")

    return new Builder<>();
  }

  /**
   * A builder for creating immutable multiset instances, especially {@code public static final}
   * multisets ("constant multisets"). Example:
   *
   * {@snippet :
   * public static final ImmutableMultiset<Bean> BEANS =
   *     new ImmutableMultiset.Builder<Bean>()
   *         .addCopies(Bean.COCOA, 4)
   *         .addCopies(Bean.GARDEN, 6)

/**
 * An immutable builder for {@link Multimap} instances, letting you independently select the desired
 * behaviors (for example, ordering) of the backing map and value-collections. Example:
 *
 * {@snippet :
 * ListMultimap<UserId, ErrorResponse> errorsByUser =
 *     MultimapBuilder.linkedHashKeys().arrayListValues().build();
 * SortedSetMultimap<String, Method> methodsForName =

  }

  /**
   * Returns {@code x mod m}, a non-negative value less than {@code m}. This differs from {@code x %
   * m}, which might be negative.
   *
   * <p>For example:
   *
   * {@snippet :
   * mod(7, 4) == 3
   * mod(-7, 4) == 1
   * mod(-1, 4) == 3
   * mod(-8, 4) == 0
   * mod(8, 4) == 0
   * }
   *
   * @throws ArithmeticException if {@code m <= 0}

 *   <li>Implementations generally do not cache hash codes. If your element or key type has a slow
 *       {@code hashCode} implementation, it should cache it itself.
 * </ul>
 *
 * <h4>Example usage</h4>
 *
 * {@snippet :
 * class Foo {
 *   private static final ImmutableSet<String> RESERVED_CODES =
 *       ImmutableSet.of("AZ", "CQ", "ZX");
 *
 *   private final ImmutableSet<String> codes;
 *

 * cache instances created by {@code CacheBuilder} will not perform any type of eviction.
 *
 * <p>Usage example:
 *
 * {@snippet :
 * LoadingCache<Key, Graph> graphs = CacheBuilder.newBuilder()
 *     .maximumSize(10000)
 *     .expireAfterWrite(Duration.ofMinutes(10))
 *     .removalListener(MY_LISTENER)
 *     .build(

   * through the returned table.
   *
   * <p>It is imperative that the user manually synchronize on the returned table when accessing any
   * of its collection views:
   *
   * {@snippet :
   * Table<R, C, V> table = Tables.synchronizedTable(HashBasedTable.create());
   * ...
   * Map<C, V> row = table.row(rowKey);  // Needn't be in synchronized block
   * ...