Java Object, interface, HLD and LLD
Hi,
I want to know why Object class is superclass for every class(not performance overhead?), why interfaces, and exact details of what is HLD and LLD.
Thanks,
Aneesh.
I want to know why Object class is superclass for every class(not performance overhead?), why interfaces, and exact details of what is HLD and LLD.
Thanks,
Aneesh.
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ASKER
Please close it off.
but have you understood the concept, is your doubt cleared?
ASKER
Actually, my ques is we are not going to use all/few methods of Object class in user class always, though it extends Object class by default. Will not this be a performance hit? What is the key point of extending Object class in user classes?
-Aneesh.
-Aneesh.
>>Will not this be a performance hit?
what makes you think that?
>>What is the key point of extending Object class in user classes?
as said, methods in Object class are required by all the classes
what makes you think that?
>>What is the key point of extending Object class in user classes?
as said, methods in Object class are required by all the classes
ASKER
>>what makes you think that?
As I extend a class(default Object class) to my class, though i dont use the methods of its super class, while creating object for my class, it will have the implementions of the Object class also rite? This is a kind of issue with resource utilzation and also access issue(performance overhead) rite?
>>as said, methods in Object class are required by all the classes
Could you tell me why is it(methods of Object class) required?
Aneesh.
As I extend a class(default Object class) to my class, though i dont use the methods of its super class, while creating object for my class, it will have the implementions of the Object class also rite? This is a kind of issue with resource utilzation and also access issue(performance overhead) rite?
>>as said, methods in Object class are required by all the classes
Could you tell me why is it(methods of Object class) required?
Aneesh.
>>while creating object for my class, it will have the implementions of the Object class also rite? This is a kind of issue with resource utilzation and also access issue(performance overhead) rite?
>>
no, there is no resource overhead on the additional methods, there will be only if the base class has some attributes/fields for which memory has to be allocated when you creat instance.
>>Could you tell me why is it(methods of Object class) required?
for example, getClass method, every instance of a class should be able to tell what type the instance is
>>
no, there is no resource overhead on the additional methods, there will be only if the base class has some attributes/fields for which memory has to be allocated when you creat instance.
>>Could you tell me why is it(methods of Object class) required?
for example, getClass method, every instance of a class should be able to tell what type the instance is
ASKER
"because Object class has the methods every class need to have!"?
and
HLD - High level design( provides high level design info )
LLD - Low level design( provides detailed design info )