@Override
    protected List<V> delegate() {
      return emptyList();
    }
  }

  @Override
  Iterator<Entry<K, V>> entryIterator() {
    throw new AssertionError("should never be called");
  }

  @Override
  Collection<Entry<K, V>> createEntries() {
    return new Entries();
  }

  @WeakOuter
  class Entries extends ForwardingCollection<Entry<K, V>> {
    @Override

    @Override
    protected List<V> delegate() {
      return emptyList();
    }
  }

  @Override
  Iterator<Entry<K, V>> entryIterator() {
    throw new AssertionError("should never be called");
  }

  @Override
  Collection<Entry<K, V>> createEntries() {
    return new Entries();
  }

  @WeakOuter
  class Entries extends ForwardingCollection<Entry<K, V>> {
    @Override

 * part of the open-source <a href="https://github.com/google/guava">Guava</a> library.
 *
 * <p>The classes in this package include:
 *
 * <h2>Immutable collections</h2>
 *
 * These are collections whose contents will never change. They also offer a few additional
 * guarantees (see {@link ImmutableCollection} for details). Implementations are available for both
 * the JDK collection types and the Guava collection types (listed below).
 *

         * negative so it with NT_STATUS_SUCCESS (0) the binary search will not be
         * performed properly. The effect is that the code at index 1 is never found
         * (NT_STATUS_UNSUCCESSFUL). So here we factor out NT_STATUS_SUCCESS
         * as a special case (which it is).
         */
        if (errcode == 0) {
            return "NT_STATUS_SUCCESS";
        }

import java.util.SortedSet;
import java.util.Spliterator;
import java.util.function.Consumer;
import java.util.stream.Collector;
import org.jspecify.annotations.Nullable;

/**
 * A {@link Set} whose contents will never change, with many other important properties detailed at
 * {@link ImmutableCollection}.
 *
 * @since 2.0
 */
@GwtCompatible
@SuppressWarnings("serial") // we're overriding default serialization

    a message. An empty string `""` is permitted. This value was never null on
    responses returned by OkHttp itself, and it was an old mistake to permit
    application code to omit a message.

 *  The challenge's scheme and realm are now non-null. If you are calling
    `new Challenge(scheme, realm)` you must provide non-null values. These were
    never null in challenges created by OkHttp, but could have been null in

          k1 ^= (long) toUnsignedInt(bb.get(1)) << 8; // fall through
        case 1:
          k1 ^= (long) toUnsignedInt(bb.get(0));
          break;
        default:
          throw new AssertionError("Should never get here.");
      }
      h1 ^= mixK1(k1);
      h2 ^= mixK2(k2);
    }

    @Override
    protected HashCode makeHash() {
      h1 ^= length;
      h2 ^= length;

      h1 += h2;

     * <p>
     * The returned instant is calculated by adding the elapsed nanoseconds
     * since clock creation to the initial wall clock time. This ensures that
     * the time never goes backwards and maintains a consistent relationship
     * with the wall clock time.
     *
     * @return the current instant using monotonic timing
     */
    @Override
    public Instant instant() {

              // positive).
              bloomFilter.put(key);
              // False negative should *never* happen.
              assertThat(bloomFilter.mightContain(key)).isTrue();

              // If this check ever fails, that means we need to either bump the
              // number of expected insertions or don't run the test for so long.

 *
 * @author Chris Nokleberg
 * @since 14.0
 */
@GwtIncompatible
public final class TestingExecutors {
  private TestingExecutors() {}

  /**
   * Returns a {@link ScheduledExecutorService} that never executes anything.
   *
   * <p>The {@code shutdownNow} method of the returned executor always returns an empty list despite
   * the fact that everything is still technically awaiting execution. The {@code getDelay} method