5 ms·

5, no? Null, Optional::empty, Optional(null), Optional(true), Optional(false)

• shagie 6mo ago
  public static void main (String[] args) { Optional<Boolean> n = Optional.ofNullable(null); Optional<Boolean> e = Optional.empty(); System.out.println(n.equals(e)); } true https://ideone.com/EGRdi5 https://ideone.com/EGRdi5 A null in an Optional is empty. So you've got: Optional<Boolean> n = null; Optional<Boolean> e = Optional.empty(); Optional<Boolean> t = Optional.of(Boolean.TRUE); Optional<Boolean> f = Optional.of(Boolean.FALSE);
  • nitnelave 6mo ago
    I guess I was missing the NPE: https://ideone.com/rp4Nvv https://ideone.com/rp4Nvv Optional.of(null) throws an NPE