what is the problems or disadvantages of using interface cla

Before coming to your answer, Let me clarify one thing i.e, "we cant use the term PROBLEMS for features".

Now coming to your question, For every feature of the oops there will be an alternate to the reuired behavior.

For example :

When do you think about Interface ?

When ever we want all our methods of class( or interface here) needs to get implemented,At that situation we needs to go for Interface & ofcourse our implemented logic can be differe from multiple derived classes.

Now coming to the PROBLEM ?

Interface cannot provide us a " CONCRETE Methods/members " which can be done with abstract class.

Programatic Explanation :

Let us think that we are having a AbcBike Company.

The "AbcBike" company feels that I'm not interested to give the implementations of the bike features like "CcEngine" or "TyreCreation"

functionalities.

Now some derived companies like "DefBike" and "GhiBike" thought to create bike but they both needs to ask "AbcBike".

But "AbcBike" company says that I will give you what are mandatory implentations(like CcEngine and TyreCreation) but I wont give you logic.

At this situation we have to make AbcBike as Interface "IAbcBike"

interface IAbcBike

{

CcEngineCreation();

TyreCreation();

}

class DefBike : IAbcBike

{

CcEngineCreation(){ //.... } // Its own logic

TyreCreation(){ //... } // Its own logic

}

class GhiBike : IAbcBike

{

CcEngineCreation() {//...} // Its own logic

TyreCreation(){ //... } // Its own logic

}

Now the disadvantage is that they cant have the common logic, Whcih can be done by abstract class.

Mark as answer, If you understand. Else come up with your query.

Thank you.