TreeMultimap<@Nullable String, @Nullable Integer> multimap = createPopulate();
    Iterator<Entry<String, Collection<Integer>>> iterator = multimap.asMap().entrySet().iterator();
    Entry<String, Collection<Integer>> entry = iterator.next();
    assertEquals(null, entry.getKey());
    assertThat(entry.getValue()).containsExactly(7, 3, 1);
    entry = iterator.next();
    assertEquals("tree", entry.getKey());

          queue.remove();
        }
      }
    }

    private static final class Event {
      private final Object event;
      private final Iterator<Subscriber> subscribers;

      private Event(Object event, Iterator<Subscriber> subscribers) {
        this.event = event;
        this.subscribers = subscribers;
      }
    }
  }

import java.util.ListIterator;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A list iterator which forwards all its method calls to another list iterator. Subclasses should
 * override one or more methods to modify the behavior of the backing iterator as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

interface GraphConnections<N, V> {

  Set<N> adjacentNodes();

  Set<N> predecessors();

  Set<N> successors();

  /**
   * Returns an iterator over the incident edges.
   *
   * @param thisNode The node that this all of the connections in this class are connected to.
   */
  Iterator<EndpointPair<N>> incidentEdgeIterator(N thisNode);

  /**

    checkNotNull(sequence);

    Iterator<String> iterator = splittingIterator(sequence);
    List<String> result = new ArrayList<>();

    while (iterator.hasNext()) {
      result.add(iterator.next());
    }

    return Collections.unmodifiableList(result);
  }

  /**
   * Splits {@code sequence} into string components and makes them available through an {@link

    public static boolean repositoriesEquals(List<RemoteRepository> r1, List<RemoteRepository> r2) {
        if (r1.size() != r2.size()) {
            return false;
        }

        for (Iterator<RemoteRepository> it1 = r1.iterator(), it2 = r2.iterator(); it1.hasNext(); ) {
            if (!repositoryEquals(it1.next(), it2.next())) {
                return false;
            }
        }

        return true;
    }

@GwtIncompatible
@ElementTypesAreNonnullByDefault
final class MultiInputStream extends InputStream {

  private Iterator<? extends ByteSource> it;
  @CheckForNull private InputStream in;

  /**
   * Creates a new instance.
   *
   * @param it an iterator of I/O suppliers that will provide each substream
   */
  public MultiInputStream(Iterator<? extends ByteSource> it) throws IOException {
    this.it = checkNotNull(it);
    advance();
  }

    TreeMultimap<String, Integer> multimap = createPopulate();
    Iterator<Entry<String, Collection<Integer>>> iterator = multimap.asMap().entrySet().iterator();
    Entry<String, Collection<Integer>> entry = iterator.next();
    assertEquals("foo", entry.getKey());
    assertThat(entry.getValue()).containsExactly(1, 3, 7);
    entry = iterator.next();
    assertEquals("google", entry.getKey());

                // care performance for List that the most frequent pattern
                final Object first = coll instanceof List<?> ? ((List<?>) coll).get(0) : coll.iterator().next();
                if (first instanceof Entity) {
                    data.register(key, coll.stream().map(BeanUtil::copyBeanToNewMap).collect(Collectors.toList()));
                    return;
                }

    }

    @Override
    public SortedMultiset<E> descendingMultiset() {
      return new StandardDescendingMultiset() {

        @Override
        Iterator<Entry<E>> entryIterator() {
          return backingMultiset.descendingMultiset().entrySet().iterator();
        }
      };
    }

    @Override
    public NavigableSet<E> elementSet() {
      return new StandardElementSet();
    }

    @Override