6 ms·

Not quite. eg: public final Date date; date.setTime(1); That's not immutable.

• lmm 12y ago
  The bean convention doesn't help you with that one though; if you have private Date date; public Date getDate() {return date;} then people can still do getDate().setTime(1);
  • cdmckay 12y ago
    Yeah, but with a getter you can make getDate return a copy of the Date object to enforce immutability.
• cakeface 12y ago
  Yeah, but getDate().setTime(1); works the same way.
  • djur 12y ago
    Not if getDate() returns a copy of the underlying member.
• mateuszf 12y ago
  Yep, the thing is that Date is immutable. I think that this public final immutable rule is ok, but one has to ensure the fields themself are really not modifiable.
  • cdmckay 12y ago
    The Java Date class is not immutable.
    • mateuszf 12y ago
      So you can use a wrapper or Joda time library.
  • brown9-2 12y ago
    A class with mutable fields that a caller can mutate is not immutable.
• nl 12y ago
  The fact that java.util.Date is terrible is so many ways should go without saying.