protected EmptyIteratorTester() {
      super(3, MODIFIABLE, Collections.<Integer>emptySet(), IteratorTester.KnownOrder.KNOWN_ORDER);
    }
  }

  @GwtIncompatible // Only used by @GwtIncompatible code
  private abstract static class SingletonIteratorTester extends IteratorTester<Integer> {
    protected SingletonIteratorTester() {
      super(3, MODIFIABLE, singleton(1), IteratorTester.KnownOrder.KNOWN_ORDER);
    }
  }

     */
    fun connectionPool(connectionPool: ConnectionPool) =
      apply {
        this.connectionPool = connectionPool
      }

    /**
     * Returns a modifiable list of interceptors that observe the full span of each call: from
     * before the connection is established (if any) until after the response source is selected
     * (either the origin server, cache, or both).
     */

    }

    /**
     * Scope the return type to {@link UnmodifiableIterator} to ensure this is an unmodifiable view.
     *
     * @since 20.0 (present with return type {@link Iterator} since 2.0)
     */
    @Override
    public abstract UnmodifiableIterator<E> iterator();
  }

  /**
   * Returns an unmodifiable <b>view</b> of the union of two sets. The returned set contains all

        this.projectProperties = unmodifiable(projectProperties);

        return this;
    }

    private static List<String> unmodifiable(List<String> list) {
        return list != null ? Collections.unmodifiableList(list) : Collections.emptyList();
    }

    private static Map<String, String> unmodifiable(Map<String, String> map) {

   * @param multiset the multiset for which an unmodifiable view is to be generated
   * @return an unmodifiable view of the multiset
   */
  public static <E extends @Nullable Object> Multiset<E> unmodifiableMultiset(
      Multiset<? extends E> multiset) {
    if (multiset instanceof UnmodifiableMultiset || multiset instanceof ImmutableMultiset) {
      @SuppressWarnings("unchecked") // Since it's unmodifiable, the covariant cast is safe

 * limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;
import static java.util.Collections.singletonList;

import com.google.common.annotations.GwtCompatible;

  }

  /**
   * Returns an unmodifiable view of the specified collection, preserving the interface for
   * instances of {@code SortedSet}, {@code Set}, {@code List} and {@code Collection}, in that order
   * of preference.
   *
   * @param collection the collection for which to return an unmodifiable view
   * @return an unmodifiable view of the collection
   */

 * limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;
import static java.util.Collections.singletonList;

import com.google.common.annotations.GwtCompatible;

      }
    }
    return true;
  }

  /**
   * Returns a {@code Collector} that returns the {@code k} smallest (relative to the specified
   * {@code Comparator}) input elements, in ascending order, as an unmodifiable {@code List}. Ties
   * are broken arbitrarily.
   *
   * <p>For example:
   *
   * <pre>{@code
   * Stream.of("foo", "quux", "banana", "elephant")
   *     .collect(least(2, comparingInt(String::length)))

  private Iterables() {}

  /** Returns an unmodifiable view of {@code iterable}. */
  public static <T extends @Nullable Object> Iterable<T> unmodifiableIterable(
      final Iterable<? extends T> iterable) {
    checkNotNull(iterable);
    if (iterable instanceof UnmodifiableIterable || iterable instanceof ImmutableCollection) {
      @SuppressWarnings("unchecked") // Since it's unmodifiable, the covariant cast is safe