assertArgumentNotNull("loader", loader);

        if (path == null || loader == null) {
            return null;
        }
        final String p = getResourcePath(path, extension);
        return loader.getResource(p);
    }

    /**
     * Returns the resource as a stream from the context class loader.
     *
     * @param path

        };

    cache.put(0, 10);

    assertThat(cache.get(0, loader)).isEqualTo(10);
    assertThat(cache.get(20, loader)).isEqualTo(1);
    assertThat(cache.get(34, loader)).isEqualTo(2);

    cache.invalidate(0);
    assertThat(cache.get(0, loader)).isEqualTo(3);

    cache.put(0, 10);
    cache.invalidateAll();
    assertThat(cache.get(0, loader)).isEqualTo(4);
  }

  @Test
  public void sizeConstraint() {

          ImmutableSet.of(
              new ResourceInfo(FILE, "left/some.txt", loader),
              new ResourceInfo(FILE, "left/sibling/another.txt", loader),
              new ResourceInfo(FILE, "right/another.txt", loader),
              new ResourceInfo(FILE, "right/sibling/some.txt", loader)),
          new ClassPath.LocationInfo(root.toFile(), loader).scanResources());
    } finally {
      deleteRecursivelyOrLog(root);
    }

    WatchedCreatorLoader loader = new WatchedCreatorLoader();
    LoadingCache<String, Integer> cache =
        CacheBuilder.newBuilder()
            .expireAfterWrite(EXPIRING_TIME, MILLISECONDS)
            .removalListener(removalListener)
            .ticker(ticker)
            .build(loader);
    checkExpiration(cache, loader, ticker, removalListener);
  }

// JoinLoaders - joins multiple loaders into a single loader. The returned
// loader will call each of the given loaders in order. If any of the loaders
// return an error, the returned loader will return that error.
func JoinLoaders(loaders ...MetricsLoaderFn) MetricsLoaderFn {
	return func(ctx context.Context, m MetricValues, c *metricsCache) error {
		for _, loader := range loaders {
			if err := loader(ctx, m, c); err != nil {
				return err
			}

  public static <K, V> CacheLoader<K, V> asyncReloading(
      CacheLoader<K, V> loader, Executor executor) {
    checkNotNull(loader);
    checkNotNull(executor);
    return new CacheLoader<K, V>() {
      @Override
      public V load(K key) throws Exception {
        return loader.load(key);
      }

      @Override
      public ListenableFuture<V> reload(K key, V oldValue) {

    assertThat(cache.localCache.defaultLoader).isSameInstanceAs(loader);
  }

  // null parameters test

  public void testNullParameters() throws Exception {
    NullPointerTester tester = new NullPointerTester();
    CacheLoader<Object, Object> loader = identityLoader();
    tester.testAllPublicInstanceMethods(makeCache(createCacheBuilder(), loader));
  }

  // stats tests

    assertThat(cache.localCache.defaultLoader).isSameInstanceAs(loader);
  }

  // null parameters test

  public void testNullParameters() throws Exception {
    NullPointerTester tester = new NullPointerTester();
    CacheLoader<Object, Object> loader = identityLoader();
    tester.testAllPublicInstanceMethods(makeCache(createCacheBuilder(), loader));
  }

  // stats tests

    IdentityLoader<Object> loader = identityLoader();
    for (int i = 1; i < 1000; i++) {
      LoadingCache<Object, Object> cache = CacheBuilder.newBuilder().maximumSize(i).build(loader);
      assertThat(CacheTesting.getTotalSegmentSize(cache)).isEqualTo(i);
    }
  }

  public void testEviction_setMaxSegmentWeight() {
    IdentityLoader<Object> loader = identityLoader();
    for (int i = 1; i < 1000; i++) {

  private final @Nullable CacheLoader<? super K, V> loader;
  private final @Nullable RemovalListener<? super K, ? super V> removalListener;
  private final StatsCounter statsCounter;
  private final Ticker ticker;
  private final long expireAfterWrite;
  private final long expireAfterAccess;

  LocalCache(
      CacheBuilder<? super K, ? super V> builder, @Nullable CacheLoader<? super K, V> loader) {
    this.loader = loader;