@Test
void ofNullable() {

    assertTrue(OptionalUtil.ofNullable(1L).isPresent());
    assertTrue(OptionalUtil.ofNullable(1).isPresent());
    assertTrue(OptionalUtil.ofNullable(1d).isPresent());
    assertTrue(OptionalUtil.ofNullable(true).isPresent());
    assertFalse(OptionalUtil.ofNullable((Long) null).isPresent());
    assertFalse(OptionalUtil.ofNullable((Integer) null).isPresent());
    assertFalse(OptionalUtil.ofNullable((Double) null).isPresent());
    assertFalse(OptionalUtil.ofNullable((Boolean) null).isPresent());
}