* supplied by the user of the class. For example, {@code Multiset.Entry.getElement()} returns
 * {@code @ParametricNullness E}, which means:
 *
 * <ul>
 *   <li>{@code getElement} on a {@code Multiset.Entry<@NonNull String>} returns {@code @NonNull
 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *

 * supplied by the user of the class. For example, {@code Multiset.Entry.getElement()} returns
 * {@code @ParametricNullness E}, which means:
 *
 * <ul>
 *   <li>{@code getElement} on a {@code Multiset.Entry<@NonNull String>} returns {@code @NonNull
 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *

          return new Multisets.AbstractEntry<E>() {
            @Override
            public E getElement() {
              return mapEntry.getKey();
            }

            @Override
            public int getCount() {
              Integer frequency = backingMap.get(getElement());
              return (frequency == null) ? 0 : frequency;
            }
          };
        }
      };

    Iterator<Entry<E>> entryIterator = entrySet().iterator();
    if (!entryIterator.hasNext()) {
      return null;
    }
    Entry<E> entry = entryIterator.next();
    return Multisets.immutableEntry(entry.getElement(), entry.getCount());
  }

  @Override
  public @Nullable Entry<E> lastEntry() {
    return delegate().lastEntry();
  }

  /**
   * A sensible definition of {@link #lastEntry()} in terms of {@code

        @SuppressWarnings("unchecked")
        Multiset.Entry<E> entry = (Entry<E>) o;
        checkArgument(
            elements.add(entry.getElement()), "Duplicate keys not allowed in EntrySetGenerator");
        for (int i = 0; i < entry.getCount(); i++) {
          contents.add(entry.getElement());
        }
      }
      return ((Multiset<E>) gen.create(contents.toArray())).entrySet();
    }

    Iterator<Entry<E>> entryIterator = entryIterator();
    if (entryIterator.hasNext()) {
      Entry<E> result = entryIterator.next();
      result = Multisets.immutableEntry(result.getElement(), result.getCount());
      entryIterator.remove();
      return result;
    }
    return null;
  }

  @Override
  public @Nullable Entry<E> pollLastEntry() {

 *     System.out.println(indexed.getElement());
 * }
 * </pre>
 *
 * <pre>
 * import static org.codelibs.core.collection.IndexedIterator.*;
 * import static org.codelibs.core.io.LineIterator.*;
 *
 * BufferedReader reader = ...;
 * for (Indexed&lt;String&gt; indexed : indexed(iterable(reader))) {
 *     System.out.println(indexed.getIndex());
 *     System.out.println(indexed.getElement());
 * }
 * </pre>
 *

        @SuppressWarnings("unchecked")
        Multiset.Entry<E> entry = (Entry<E>) o;
        checkArgument(
            elements.add(entry.getElement()), "Duplicate keys not allowed in EntrySetGenerator");
        for (int i = 0; i < entry.getCount(); i++) {
          contents.add(entry.getElement());
        }
      }
      return ((Multiset<E>) gen.create(contents.toArray())).entrySet();
    }

      }

      @Override
      public E next() {
        if (remaining <= 0) {
          Entry<E> entry = entryIterator.next();
          element = entry.getElement();
          remaining = entry.getCount();
        }
        remaining--;
        /*
         * requireNonNull is safe because `remaining` starts at 0, forcing us to initialize

          ToOptionalState::new,
          (state, o) -> state.add((o == null) ? NULL_PLACEHOLDER : o),
          ToOptionalState::combine,
          state -> {
            Object result = state.getElement();
            return (result == NULL_PLACEHOLDER) ? null : result;
          },
          Collector.Characteristics.UNORDERED);

  /**