super(new Object(), frq);
    }

    @Override
    public void finalizeReferent() {
      finalizeReferentCalled = true;
    }
  }

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;

      this.queue = new ArrayDeque<>();
      queue.add(root);
    }

    @Override
    public boolean hasNext() {
      return !queue.isEmpty();
    }

    @Override
    public T peek() {
      return queue.element();
    }

    @Override
    public T next() {
      T result = queue.remove();
      Iterables.addAll(queue, children(result));
      return result;
    }
  }

   */
  @GwtIncompatible // java.lang.ref.WeakReference
  @CanIgnoreReturnValue
  public CacheBuilder<K, V> weakKeys() {
    return setKeyStrength(Strength.WEAK);
  }

  @CanIgnoreReturnValue
  CacheBuilder<K, V> setKeyStrength(Strength strength) {
    checkState(keyStrength == null, "Key strength was already set to %s", keyStrength);

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.InlineMe;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.Weak;
import com.google.j2objc.annotations.WeakOuter;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.AbstractCollection;

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.InlineMe;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.Weak;
import com.google.j2objc.annotations.WeakOuter;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.AbstractCollection;

        }

        validClasses.add(new WeakReference<Class<? extends Exception>>(exceptionClass));
      }
    }

    /**
     * Returns the ClassValue-using validator, or falls back to the "weak Set" implementation if
     * unable to do so.
     */
    static GetCheckedTypeValidator getBestValidator() {
      return weakSetValidator();
    }
  }

import com.google.errorprone.annotations.DoNotCall;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.RetainedWith;
import com.google.j2objc.annotations.Weak;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Comparator;
import java.util.Map;

  fun dispatcherFromMockWebServer() {
    val dispatcher =
      object : okhttp3.mockwebserver.Dispatcher() {
        override fun dispatch(request: RecordedRequest): MockResponse = TODO()

        override fun peek(): MockResponse = TODO()

        override fun shutdown() = TODO()
      }
  }

  @Test
  fun dns() {
    var dns: Dns = Dns { TODO() }

    val system: Dns = Dns.SYSTEM
  }

    BlockingQueue<String> queue = new ArrayBlockingQueue<>(999);
    putUninterruptibly(queue, "");
    assertTimeNotPassed(stopwatch, LONG_DELAY_MS);
    assertEquals("", queue.peek());
  }

  public void testPutNoInterrupt() {
    TimedPutQueue queue = TimedPutQueue.createWithDelay(20);
    queue.putSuccessfully();
    assertNotInterrupted();
  }

    Iterator<Integer> consumingIterator = Iterables.consumingIterable(queue).iterator();

    assertEquals(5, queue.peek().intValue());
    assertEquals(5, consumingIterator.next().intValue());

    assertEquals(14, queue.peek().intValue());
    assertTrue(consumingIterator.hasNext());
    assertTrue(queue.isEmpty());
  }

  public void testConsumingIterable_noIteratorCall() {