static IncrementingLoader incrementingLoader() {
    return new IncrementingLoader();
  }

  /** Returns a {@link CacheLoader} that throws the given error for every request. */
  static <K, V> CacheLoader<K, V> errorLoader(Error e) {
    checkNotNull(e);
    return new CacheLoader<K, V>() {
      @Override
      public V load(K key) {
        throw e;
      }
    };
  }

  static IncrementingLoader incrementingLoader() {
    return new IncrementingLoader();
  }

  /** Returns a {@link CacheLoader} that throws the given error for every request. */
  static <K, V> CacheLoader<K, V> errorLoader(Error e) {
    checkNotNull(e);
    return new CacheLoader<K, V>() {
      @Override
      public V load(K key) {
        throw e;
      }
    };
  }

import static com.google.common.cache.TestingCacheLoaders.bulkLoader;
import static com.google.common.cache.TestingCacheLoaders.constantLoader;
import static com.google.common.cache.TestingCacheLoaders.errorLoader;
import static com.google.common.cache.TestingCacheLoaders.exceptionLoader;
import static com.google.common.cache.TestingCacheLoaders.identityLoader;

import static com.google.common.cache.TestingCacheLoaders.bulkLoader;
import static com.google.common.cache.TestingCacheLoaders.constantLoader;
import static com.google.common.cache.TestingCacheLoaders.errorLoader;
import static com.google.common.cache.TestingCacheLoaders.exceptionLoader;
import static com.google.common.cache.TestingCacheLoaders.identityLoader;

        assertEquals(0, responseRef.get().getNumberOfInputDocs());
    }

    @Test
    public void test_indexFromQueryLogReaderWithErrorThrowingReader() throws Exception {
        QueryLogReader errorReader = new QueryLogReader() {
            @Override
            public QueryLog read() {
                throw new RuntimeException("Simulated read error");
            }

            @Override