Iterator<Entry<K, V>> entryIterator = backingMap.entrySet().iterator();

        return new UnmodifiableIterator<K>() {
          @Override
          public boolean hasNext() {
            return entryIterator.hasNext();
          }

          @Override
          public K next() {
            Entry<K, V> entry = entryIterator.next(); // store local reference for thread-safety

      remaining = biMap.size();
    }

    @Override
    public final boolean hasNext() {
      if (biMap.modCount != expectedModCount) {
        throw new ConcurrentModificationException();
      }
      return next != null && remaining > 0;
    }

    @Override
    public final T next() {
      if (!hasNext()) {
        throw new NoSuchElementException();
      }

         * throwing an IllegalStateException.
         */
        return new Iterator<T>() {
          boolean atStart = true;

          @Override
          public boolean hasNext() {
            return iterator.hasNext();
          }

          @Override
          @ParametricNullness
          public T next() {
            T result = iterator.next();

      this.iterator = iterable.iterator();
    }

    @Override
    public boolean hasNext() {
      return true; // pretend that you have more...
    }

    @Override
    public E next() {
      // ...but throw an unchecked exception when you ask for it.
      if (!iterator.hasNext()) {
        throw new ThrowsAtEndException();
      }
      return iterator.next();
    }

    private int nextIndex;

    /**
     * nextItem holds on to item fields because once we claim that an element exists in hasNext(),
     * we must return it in the following next() call even if it was in the process of being removed
     * when hasNext() was called.
     */
    private @Nullable E nextItem;

    /**

    while (keyValues.hasNext() && newValues.hasNext()) {
      keyValues.next();
      keyValues.set(newValues.next());
    }

    // Remove remaining old values, if any.
    while (keyValues.hasNext()) {
      keyValues.next();
      keyValues.remove();
    }

    // Add remaining new values, if any.
    while (newValues.hasNext()) {
      keyValues.add(newValues.next());
    }

      this.iterator = iterable.iterator();
    }

    @Override
    public boolean hasNext() {
      return true; // pretend that you have more...
    }

    @Override
    public E next() {
      // ...but throw an unchecked exception when you ask for it.
      if (!iterator.hasNext()) {
        throw new ThrowsAtEndException();
      }
      return iterator.next();
    }

    assertFalse(cycle.iterator().hasNext());
  }

  public void testCycle_removingAllElementsStopsCycle() {
    FluentIterable<Integer> cycle = fluent(1, 2).cycle();
    Iterator<Integer> iterator = cycle.iterator();
    iterator.next();
    iterator.remove();
    iterator.next();
    iterator.remove();
    assertFalse(iterator.hasNext());
    assertFalse(cycle.iterator().hasNext());
  }

   *
   * @param failedConnection an optional connection that was resulted in a failure. If the failure
   *     is recoverable, the connection's route may be recovered for the retry.
   */
  fun hasNext(failedConnection: RealConnection? = null): Boolean

  /**
   * Returns true if the host and port are unchanged from when this was created. This is used to

        // Assert: first page
        assertTrue(it.hasNext(), "Iterator should have first element");
        assertSame(fe1, it.next(), "First element must match first page");
        assertTrue(it.hasNext(), "Iterator should have second element");
        assertSame(fe2, it.next(), "Second element must match first page");

        // Next page fetched via fetchMore()
        assertTrue(it.hasNext(), "Iterator should have third element after fetchMore");