* overridden as desired.
 *
 * <p>Usage example:
 *
 * {@snippet :
 * CacheLoader<Key, Graph> loader = new CacheLoader<Key, Graph>() {
 *   public Graph load(Key key) throws AnyException {
 *     return createExpensiveGraph(key);
 *   }
 * };
 * LoadingCache<Key, Graph> cache = CacheBuilder.newBuilder().build(loader);
 * }
 *

   * {@code key}, simply waits for that thread to finish and returns its loaded value. Note that
   * multiple threads can concurrently load values for distinct keys.
   *
   * <p>Caches loaded by a {@link CacheLoader} will call {@link CacheLoader#load} to load new values
   * into the cache. Newly loaded values are added to the cache using {@code

   *
   * When we reference FinalizableReferenceQueue in this test, we are referencing a class that is
   * loaded by this test and that will obviously remain loaded for as long as the test is running.
   * So in order to check ClassLoader garbage collection we need to create a new ClassLoader and
   * make it load its own version of FinalizableReferenceQueue. Then we need to interact with that

   *
   * If the library is loaded in an application class loader, we try to break the cycle by loading
   * Finalizer in its own independent class loader:
   *
   * System class loader -> Application class loader -> ReferenceMap -> FinalizableReferenceQueue ->
   * etc. -> Decoupled class loader -> Finalizer
   *

      this.file = checkNotNull(file);
      this.resourceName = checkNotNull(resourceName);
      this.loader = checkNotNull(loader);
    }

    /**
     * Returns the url identifying the resource.
     *
     * <p>See {@link ClassLoader#getResource}
     *
     * @throws NoSuchElementException if the resource cannot be loaded through the class loader,
     *     despite physically existing in the class path.

 * loader. That way, this class doesn't prevent the main class loader from getting garbage
 * collected, and this class can detect when the main class loader has been garbage collected and
 * stop itself.
 */
public class Finalizer implements Runnable {

  private static final Logger logger = Logger.getLogger(Finalizer.class.getName());

  /**

    CountingLoader loader = new CountingLoader();
    LocalCache<Object, Object> map = makeLocalCache(createCacheBuilder());
    assertThat(loader.getCount()).isEqualTo(0);

    Object key = new Object();
    Object value = map.get(key, loader);
    assertThat(loader.getCount()).isEqualTo(1);
    assertThat(map.get(key, loader)).isEqualTo(value);
    assertThat(loader.getCount()).isEqualTo(1);
  }

    CountingLoader loader = new CountingLoader();
    LocalCache<Object, Object> map = makeLocalCache(createCacheBuilder());
    assertThat(loader.getCount()).isEqualTo(0);

    Object key = new Object();
    Object value = map.get(key, loader);
    assertThat(loader.getCount()).isEqualTo(1);
    assertThat(map.get(key, loader)).isEqualTo(value);
    assertThat(loader.getCount()).isEqualTo(1);
  }

        CacheBuilder<? super K, ? super V> builder, @Nullable CacheLoader<? super K, V> loader) {
      localCache = new LocalCache<K, V>(builder, loader);
    }

    // Cache methods

    @Override
    public V get(K key, Callable<? extends V> valueLoader) throws ExecutionException {
      synchronized (localCache.lock) { // Prevent concurrent loads for the same key
        V value = localCache.get(key);
        if (value != null) {

   * {@link CacheLoader#load} calls to {@code loader}.
   */
  static <K, V> CacheLoader<K, V> bulkLoader(CacheLoader<K, V> loader) {
    checkNotNull(loader);
    return new CacheLoader<K, V>() {
      @Override
      public V load(K key) throws Exception {
        return loader.load(key);
      }

      @Override