Comparing user defined classes ???

class A
     int i=10;
class B
     int i=10;
     //int k = 30;
As we compare both primitive variables,
Is it possible to compare the above A and B classes.
since A and B consists of same variable and same data,
i should get o/p as both are same.
Is it possible to compare like this(classes) ????
but when i remove comment from Class B
the o/p should be both are not same.
with out making a single change in the code. is it possible ?????
i tried it with Comparator...but code need to be change when i remove comment from Class B.

Waitaminnit.
What you're asking for doesn't make any sense.
You want class A and class B to compare a certain way, but then if you change the code for class B, you want them to compare a different way, without changing any other code?
That's fairly ridiculous. Whatever is doing the comparing should know a priori about the important stuff in class B. You can't just come along later and change class B such that the set of important stuff is now different and expect other code to magically know this.
I suppose you could have the Comparator do some weird, ugly-asss reflection and apply some rules to its result, but ick.
Also, you shouldn't even be trying to compare A and B unless one descends from the other, or they descend from a commom ancestor that has all the fields you're going to use in the comparison.
For instance, if B extends A, then you can get rid of the i in B. The comparison would be implemented on A only, and would treat everything as an A. This works because a B is an A.

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Hi All,
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Regards,

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Whats the implementation logic with strings as
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Regards,I don't understand the question.

Comparing a user defined class

Hi
I've defined a class called Customer, and when i make two instances of it, i want to compare them to see if they are equal or not. To do this, do i have to write my own equals() method for the class, or is there an easier way to do it?
cheers for the help
Sok

Hi
I've defined a class called Customer, and when i make
two instances of it, i want to compare them to see if
they are equal or not. To do this, do i have to write
my own equals() method for the class, or is there an
easier way to do it?
cheers for the help
SokThat is the accepted way of doing it!

Comparing user defined classes ???

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