// if the iterators don't support remove
        return Sets.removeAllImpl(this, c.iterator());
      }
    }

    @Override
    public boolean retainAll(Collection<?> c) {
      try {
        return super.retainAll(checkNotNull(c));
      } catch (UnsupportedOperationException e) {
        // if the iterators don't support remove

          ReferenceEntry<K, V> next = previous.getNextInAccessQueue();
          return (next == head) ? null : next;
        }
      };
    }
  }

  // Cache support

  public void cleanUp() {
    for (Segment<?, ?> segment : segments) {
      segment.cleanUp();
    }
  }

  // ConcurrentMap methods

  @Override
  public boolean isEmpty() {

          ReferenceEntry<K, V> next = previous.getNextInAccessQueue();
          return (next == head) ? null : next;
        }
      };
    }
  }

  // Cache support

  public void cleanUp() {
    for (Segment<?, ?> segment : segments) {
      segment.cleanUp();
    }
  }

  // ConcurrentMap methods

  @Override
  public boolean isEmpty() {

            .named("LocalCache with defaults")
            .withFeatures(
                CollectionSize.ANY,
                MapFeature.GENERAL_PURPOSE,
                CollectionFeature.SUPPORTS_ITERATOR_REMOVE)
            .createTestSuite());
    suite.addTest(
        ConcurrentMapTestSuiteBuilder.using(
                new TestStringCacheGenerator(createCacheBuilder().concurrencyLevel(1)))

            .named("LocalCache with defaults")
            .withFeatures(
                CollectionSize.ANY,
                MapFeature.GENERAL_PURPOSE,
                CollectionFeature.SUPPORTS_ITERATOR_REMOVE)
            .createTestSuite());
    suite.addTest(
        ConcurrentMapTestSuiteBuilder.using(
                new TestStringCacheGenerator(createCacheBuilder().concurrencyLevel(1)))

     * your current SDK version but also at the oldest version you support. For example, <a
     * href="https://developer.android.com/sdk/api_diff/16/">API Level 16</a> is the first version
     * in which {@code Cursor} is {@code Closeable}. To support older versions, pass a wrapper
     * {@code Closeable} with a method reference like {@code cursor::close}.
     *