assertThat(Optional.of("training").get()).isEqualTo("training");
  }

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

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

  public void testFromNullable_null() {
    // not promised by spec, but easier to test