hashCode()

You don't. It's the other way around. If you override equals, you should override hashCode.

See the contract specified in Object.

[url]

http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html

[/url]

If you override equals so that two distinct objects can be considered equal values and thus equals returns true for them, then you have to ensure that hashCode also returns the same value for both objects.

If you override equals but not hashCode, you cannot maintain this contract. But you can override hashCode alone (for example, make it always return 13) without breaking the contract.

The reason for this is the way Hashtables work; if you override equals but not hashCode, they won't; if you override hashCode as I said above, everything will work but it will be slow, very slow indeed.

Lokoa at 2007-7-14 1:11:43 >