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JavaRanch » Java Forums » Certification » Programmer Certification (SCJP/OCPJP)
Bookmark "equals(object)" Watch "equals(object)" New topic


yamini nadella
Ranch Hand

Joined: Apr 13, 2004
Posts: 257
If equals() of two object is true then those Hashcodes must be True.
Vice versa is also correct?
If hashcodes of two objects are same then equals(obj) becomes true ?
Corey McGlone
Ranch Hand

Joined: Dec 20, 2001
Posts: 3271
No, the inverse is not true. If you look at the API Spec for Object, you'd see this under the description of the hashcode method:

It is not required that if two objects are unequal according to the equals(java.lang.Object) method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hashtables.


SCJP Tipline, etc.
I agree. Here's the link:
subject: equals(object)