boolean sameComparator,
      Iterable<? extends Entry<? extends K, ? extends V>> entries) {
    // "adding" type params to an array of a raw type should be safe as
    // long as no one can ever cast that same array instance back to a
    // raw type.
    @SuppressWarnings("unchecked")
    Entry<K, V>[] entryArray = (Entry[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);

   * java.util.TreeMap}).
   *
   * <p>Each method invocation on the set returned by this method results in exactly one method
   * invocation on the backing map or its {@code keySet} view, with one exception. The {@code
   * addAll} method is implemented as a sequence of {@code put} invocations on the backing map.
   *

    Iterator<String> iterator = asList("one", "two").iterator();
    try {
      Iterators.getOnlyElement(iterator);
      fail();
    } catch (IllegalArgumentException expected) {
      assertThat(expected).hasMessageThat().isEqualTo("expected one element but was: <one, two>");
    }
  }

  public void testGetOnlyElement_noDefault_fiveElements() {

  /**
   * Returns a multimap view of the specified map. The multimap is backed by the map, so changes to
   * the map are reflected in the multimap, and vice versa. If the map is modified while an
   * iteration over one of the multimap's collection views is in progress (except through the
   * iterator's own {@code remove} operation, or through the {@code setValue} operation on a map

         * element anymore. Otherwise, when we remove from the old iterator, we may be invalidating
         * the new one. The result is a ConcurrentModificationException or other bad behavior.
         *
         * (If we decide that we really, really hate allocating two Iterators per cycle instead of
         * one, we can optimistically store the new Iterator and then be willing to throw it out if
         * the user calls remove().)