public SomeAbstractClass() {}
  }

  static class NonPublicClass {
    public NonPublicClass() {}
  }

  private static class WithPrivateConstructor {
    @Keep public static final WithPrivateConstructor INSTANCE = new WithPrivateConstructor();
  }

  public static class NoDefaultConstructor {
    public NoDefaultConstructor(@SuppressWarnings("unused") int i) {}
  }