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

/** An ordering which sorts iterables by comparing corresponding elements pairwise. */
@GwtCompatible(serializable = true)
@ElementTypesAreNonnullByDefault
final class LexicographicalOrdering<T extends @Nullable Object> extends Ordering<Iterable<T>>
    implements Serializable {