Optional<String> optionalName = Optional.absent();
    assertFalse(optionalName.isPresent());
  }

  public void testOf() {
    assertEquals("training", Optional.of("training").get());
  }

  public void testOf_null() {
    assertThrows(NullPointerException.class, () -> Optional.of(null));
  }

  public void testFromNullable() {
    Optional<String> optionalName = Optional.fromNullable("bob");