hashCode(), compareTo() and equals()

[shuba karthik]

Are these methods related by any means?

[Barry Gaunt]

Such vague questions are not very helpful. What have you read about the methods that you do not understand?

Read this if you have nothing else.
[ August 27, 2005: Message edited by: Barry Gaunt ]

[Shivani Chandna]

Yes.

** Equal objects must have equal hash codes.

And

** If the 2 objects are returning 0 using compareTo() then they must return true using equal() as well given that the objects are mantained in a sorted map. (Where Comparable interface is overrided if needed to be).

[Akshay Kiran]

See the Discussion for the methods equals() and hashCode() in the java API documentation under the class "Object" that is by far the best guide you can get.

[shuba karthik]

if equals() return true should compareTo() return 0

[wise owen]

Yes.
The compareTo() method will return a negative number, zero, or positive number depending on whether the Object is less than, equal to, or greater than the Object argument. It is recommended that Objects that implement the compareTo() should ensure that if the equals() method of the Object return true then the same comparison using compareTo( ) should return zero.