question is not clear
may ur question is 
why hashcode() will be override when u override equals()? 
is it

equals method available in object class is for address
comparison not  for  content comparison.so for content
comparison we have to override equals method in our class.
wrapper classes and string class has overridden equals
method for content comparison.

to check if 2 objects references to the same memory 
location..

equals() method will be available in primodian class that is
Object class, but by default it compares only the addresses,
not the contents, So if you want the content comparison you
have to override equals(), but if u override the equals(),
you have to override the hashCode() also.