*
   * <p>For streams with defined encounter order (as defined in the Ordering section of the {@link
   * java.util.stream} Javadoc), that order is preserved, but entries are <a
   * href="ImmutableMultimap.html#iteration">grouped by key</a>.
   *
   * <p>Example:
   *
   * <pre>{@code
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")

      boolean hasSetRunning = false;
      try {
        while (true) {
          synchronized (queue) {
            // Choose whether this thread will run or not after acquiring the lock on the first
            // iteration
            if (!hasSetRunning) {
              if (workerRunningState == RUNNING) {
                // Don't want to have two workers pulling from the queue.
                return;
              } else {

      boolean hasSetRunning = false;
      try {
        while (true) {
          synchronized (queue) {
            // Choose whether this thread will run or not after acquiring the lock on the first
            // iteration
            if (!hasSetRunning) {
              if (workerRunningState == RUNNING) {
                // Don't want to have two workers pulling from the queue.
                return;
              } else {

   *     iterator().next()} or {@link Iterables#getFirst} instead.
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final Optional<@NonNull E> first() {
    Iterator<E> iterator = getDelegate().iterator();
    return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.absent();
  }

  /**

   * IllegalArgumentException}.
   */
  boolean allowsSelfLoops();

  /** Returns the order of iteration for the elements of {@link #nodes()}. */
  ElementOrder<N> nodeOrder();

  /** Returns the order of iteration for the elements of {@link #edges()}. */
  ElementOrder<E> edgeOrder();

  //
  // Element-level accessors
  //

  /**

    }
    try {
      Iterator<Integer> iterator = unmod.iterator();
      iterator.next();
      iterator.remove();
      fail("UnsupportedOperationException expected");
    } catch (UnsupportedOperationException expected) {
    }
    try {
      Iterator<Integer> iterator = unmod.descendingIterator();
      iterator.next();
      iterator.remove();

    }

    @Override
    public boolean isEmpty() {
      return !Iterables.any(unfiltered, predicate);
    }

    @Override
    public Iterator<E> iterator() {
      return Iterators.filter(unfiltered.iterator(), predicate);
    }

    @Override
    public Spliterator<E> spliterator() {
      return CollectSpliterators.filter(unfiltered.spliterator(), predicate);
    }

    }
    return (node == header || !range.contains(node.getElement())) ? null : node;
  }

  @Override
  Iterator<E> elementIterator() {
    return Multisets.elementIterator(entryIterator());
  }

  @Override
  Iterator<Entry<E>> entryIterator() {
    return new Iterator<Entry<E>>() {
      @CheckForNull AvlNode<E> current = firstNode();
      @CheckForNull Entry<E> prevEntry;

      @Override

import java.util.Spliterators;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * CompactLinkedHashMap is an implementation of a Map with insertion or LRU iteration order,
 * maintained with a doubly linked list through the entries. All optional operations (put and
 * remove) are supported. Null keys and values are supported.
 *

   *
   * <p>For streams with defined encounter order (as defined in the Ordering section of the {@link
   * java.util.stream} Javadoc), that order is preserved, but entries are <a
   * href="ImmutableMultimap.html#iteration">grouped by key</a>.
   *
   * <p>Example:
   *
   * <pre>{@code
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")