This page contains an archived post to the Design Forum (formerly called the Flexible Java Forum) made prior to February 25, 2002. If you wish to participate in discussions, please visit the new Artima Forums.

Message:

hashCode() should be overridden with equals()

Posted by Jody Justus on 15 Sep 1998, 10:05 AM

Quoting the docs:

"If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result."

Otherwise, the object will not work properly as an element of a hashed collection (Set) or as a key in a hashtable.

See:
http://java.sun.com/products/jdk/1.1/docs/api/java.lang.Object.html#hashCode()
http://java.sun.com/products/jdk/1.1/docs/api/java.lang.Object.html#equals(java.lang.Object)

- -- J

• By George, You're Right! Bill Venners 16 Sep 1998, 1:19 AM (0)