final Queue<RemovalNotification<K, V>> removalNotificationQueue;

  /**
   * A listener that is invoked when an entry is removed due to expiration or garbage collection of
   * soft/weak entries.
   */
  final RemovalListener<K, V> removalListener;

  /** Measures time in a testable way. */
  final Ticker ticker;

 *   <li>least-recently-used eviction when a maximum size is exceeded (note that the cache is
 *       divided into segments, each of which does LRU internally)
 *   <li>time-based expiration of entries, measured since last access or last write
 *   <li>keys automatically wrapped in {@code WeakReference}
 *   <li>values automatically wrapped in {@code WeakReference} or {@code SoftReference}

import java.util.Set;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import junit.framework.TestCase;

/**
 * Tests relating to cache expiration: make sure entries expire at the right times, make sure
 * expired entries don't show up, etc.
 *
 * @author mike nonemacher
 */
@SuppressWarnings("deprecation") // tests of deprecated method

 *   <li>least-recently-used eviction when a maximum size is exceeded (note that the cache is
 *       divided into segments, each of which does LRU internally)
 *   <li>time-based expiration of entries, measured since last access or last write
 *   <li>keys automatically wrapped in {@code WeakReference}
 *   <li>values automatically wrapped in {@code WeakReference} or {@code SoftReference}

  }

  /**
   * Calls get() repeatedly from many different threads, and tests that all of the removed entries
   * (removed because of size limits or expiration) trigger appropriate removal notifications.
   */
  @GwtIncompatible // QueuingRemovalListener

  public void testRemovalNotification_get_basher() throws InterruptedException {
    int nTasks = 1000;

   * value after the specified time has passed. Subsequent calls to {@code get()} return the cached
   * value if the expiration time has not passed. After the expiration time, a new value is
   * retrieved, cached, and returned. See: <a
   * href="http://en.wikipedia.org/wiki/Memoization">memoization</a>
   *

  final Queue<RemovalNotification<K, V>> removalNotificationQueue;

  /**
   * A listener that is invoked when an entry is removed due to expiration or garbage collection of
   * soft/weak entries.
   */
  final RemovalListener<K, V> removalListener;

  /** Measures time in a testable way. */
  final Ticker ticker;

 * never be removed.
 *
 * <p>Durations are represented by an integer, followed by one of "d", "h", "m", or "s",
 * representing days, hours, minutes, or seconds respectively. (There is currently no syntax to
 * request expiration in milliseconds, microseconds, or nanoseconds.)
 *
 * <p>Whitespace before and after commas and equal signs is ignored. Keys may not be repeated; it is
 * also illegal to use the following pairs of keys in a single value:
 *

  }

  /**
   * Calls get() repeatedly from many different threads, and tests that all of the removed entries
   * (removed because of size limits or expiration) trigger appropriate removal notifications.
   */
  @GwtIncompatible // QueuingRemovalListener

  public void testRemovalNotification_get_basher() throws InterruptedException {
    int nTasks = 1000;