@NullUnmarked
public class SourceSinkTester<S, T, F extends SourceSinkFactory<S, T>> extends TestCase {

  static final String LOREM_IPSUM =
      "Lorem ipsum dolor sit amet, consectetur adipiscing "
          + "elit. Cras fringilla elit ac ipsum adipiscing vulputate. Maecenas in lorem nulla, ac "
          + "sollicitudin quam. Praesent neque elit, sodales quis vestibulum vel, pellentesque nec "