}
  }

  private interface Adder {
    int add(int a, int b);
  }

  private static class ForwardingArithmetic implements Arithmetic {
    private final Arithmetic arithmetic;

    public ForwardingArithmetic(Arithmetic arithmetic) {
      this.arithmetic = arithmetic;
    }

    @Override
    public int add(int a, int b) {
      return arithmetic.add(a, b);
    }

    @Override

    assertNull(map.getInstance(int.class));
    assertNull(map.getInstance(Integer.class));

    assertNull(map.putInstance(int.class, 0));
    assertNull(map.putInstance(Integer.class, 1));
    assertEquals(2, map.size());

    assertEquals(0, (int) map.getInstance(int.class));
    assertEquals(1, (int) map.getInstance(Integer.class));

    assertEquals(0, (int) map.putInstance(int.class, null));

    private final long timeout;
    private final TimeUnit unit;
    private Exception exception;
    private volatile long startTime;
    private long timeSpentBlocked;

    TimedWaiterThread(AbstractFuture<?> future, long timeout, TimeUnit unit) {
      this.future = future;
      this.timeout = timeout;
      this.unit = unit;
    }

    @Override
    public void run() {

  }

  public void testCheckPositive_minInt() {
    assertThrows(
        IllegalArgumentException.class,
        () -> MathPreconditions.checkPositive("int", Integer.MIN_VALUE));
  }

  public void testCheckPositive_positiveInt() {
    MathPreconditions.checkPositive("int", 1);
  }

  public void testCheckPositive_negativeInt() {

  public void testFastAddAllMultiset() {
    final AtomicInteger addCalls = new AtomicInteger();
    Multiset<String> multiset =
        new NoRemoveMultiset<String>() {
          @Override
          public int add(String element, int occurrences) {
            addCalls.incrementAndGet();
            return super.add(element, occurrences);
          }
        };
    ImmutableMultiset<String> adds =

        }
        return cancelled;
      }

      @Override
      public long getDelay(TimeUnit unit) {
        return scheduledDelegate.getDelay(unit);
      }

      @Override
      public int compareTo(Delayed other) {
        return scheduledDelegate.compareTo(other);
      }
    }

    @J2ktIncompatible
    @GwtIncompatible // TODO

   * @param unit the time unit of the timeout argument
   * @return {@code true} if the permits were acquired, {@code false} otherwise
   * @throws IllegalArgumentException if the requested number of permits is negative or zero
   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  public boolean tryAcquire(int permits, long timeout, TimeUnit unit) {

  @Override
  public int drainTo(Collection<? super E> c, int maxElements) {
    if (c == null) throw new NullPointerException();
    if (c == this) throw new IllegalArgumentException();
    if (maxElements <= 0) return 0;
    final Monitor monitor = this.monitor;
    monitor.enter();
    try {
      int n = 0;
      E e;
      while (n < maxElements && (e = q.poll()) != null) {

   */
  @CanIgnoreReturnValue
  @Override
  public int drainTo(Collection<? super E> c) {
    if (c == null) throw new NullPointerException();
    if (c == this) throw new IllegalArgumentException();
    final E[] items = this.items;
    final Monitor monitor = this.monitor;
    monitor.enter();
    try {
      int i = takeIndex;
      int n = 0;
      int max = count;
      while (n < max) {
        c.add(items[i]);

  @CanIgnoreReturnValue
  public CacheBuilder<K, V> refreshAfterWrite(long duration, TimeUnit unit) {
    checkNotNull(unit);
    checkState(refreshNanos == UNSET_INT, "refresh was already set to %s ns", refreshNanos);
    checkArgument(duration > 0, "duration must be positive: %s %s", duration, unit);
    this.refreshNanos = unit.toNanos(duration);
    return this;
  }