*   <li>{@link ImmutableSortedMultiset}
 *   <li>{@link HashMultiset}
 *   <li>{@link LinkedHashMultiset}
 *   <li>{@link TreeMultiset}
 *   <li>{@link EnumMultiset}
 *   <li>{@link ConcurrentHashMultiset}
 * </ul>
 *
 * <p>If your values may be zero, negative, or outside the range of an int, you may wish to use
 * {@link com.google.common.util.concurrent.AtomicLongMap} instead. Note, however, that unlike