/**
* Returns the element at the specified position in an iterable or a default value otherwise.
*
* @param position position of the element to return
* @param defaultValue the default value to return if {@code position} is greater than or equal to
* the size of the iterable
* @return the element at the specified position in {@code iterable} or {@code defaultValue} if
* {@code iterable} contains fewer than {@code position + 1} elements.
* @throws IndexOutOfBoundsException if {@code position} is negative
* @since 4.0
*/
@Nullable
public static <T> T get(Iterable<? extends T> iterable, int position, @Nullable T defaultValue) {
checkNotNull(iterable);
Iterators.checkNonnegative(position);
if (iterable instanceof List) {
List<? extends T> list = Lists.cast(iterable);
return (position < list.size()) ? list.get(position) : defaultValue;
} else {
Iterator<? extends T> iterator = iterable.iterator();
Iterators.advance(iterator, position);
return Iterators.getNext(iterator, defaultValue);
}
}
/**
* Returns the first element in {@code iterable} or {@code defaultValue} if the iterable is empty.
* The {@link Iterators} analog to this method is {@link Iterators#getNext}.
*
* <p>If no default value is desired (and the caller instead wants a {@link
* NoSuchElementException} to be thrown), it is recommended that {@code
* iterable.iterator().next()} is used instead.
*
* @param defaultValue the default value to return if the iterable is empty
* @return the first element of {@code iterable} or the default value
* @since 7.0
*/
@Nullable
public static <T> T getFirst(Iterable<? extends T> iterable, @Nullable T defaultValue) {
return Iterators.getNext(iterable.iterator(), defaultValue);
}
/** @since 12.0 */
@GwtIncompatible("NavigableSet")
@Override
public E floor(E e) {
return Iterators.getNext(headSet(e, true).descendingIterator(), null);
}