- Can we declare abstract class as final?
- Can abstract class have constructor C++?
- Why abstract classes can not be instantiated?
- What is the point of an abstract class?
- Does abstract method have body?
- Can an abstract class be private?
- Can we declare abstract class as static?
- Can we inherit one abstract class to another abstract class?
- Is it possible to inherit from multiple abstract classes in Java?
- Can a abstract class have constructor?
- What happens if we create object of abstract class?
- Can we inherit abstract class?
Can we declare abstract class as final?
In short, an abstract class cannot be final in Java, using both abstract and final modifier with a class is illegal in Java.
An abstract method must be overridden to be useful and called but when you make the abstract method final it cannot be overridden in Java, hence there would be no way to use that method..
Can abstract class have constructor C++?
An abstract class can have constructor similar to normal class implementation. In the case of the destructor, we can declare a pure virtual destructor. It is important to have a destructor to delete the memory allocated for the class.
Why abstract classes can not be instantiated?
Because an abstract class is an incomplete class (incomplete in the sense it contains abstract methods without body and output) we cannot create an instance or object; the same way you say for an interface. You CAN instantiate an abstract class. You only need to provide a concrete subclass.
What is the point of an abstract class?
The purpose of an abstract class is to define some common behavior that can be inherited by multiple subclasses, without implementing the entire class.
Does abstract method have body?
Abstract methods means there is no default implementation for it and an implementing class will provide the details. So, it’s exactly as the error states: your abstract method can not have a body. The reason you would do something like this is if multiple objects can share some behavior, but not all behavior.
Can an abstract class be private?
If a method of a class is private, you cannot access it outside the current class, not even from the child classes of it. But, incase of an abstract method, you cannot use it from the same class, you need to override it from subclass and use. Therefore, the abstract method cannot be private.
Can we declare abstract class as static?
Yes, abstract class can have Static Methods. The reason for this is Static methods do not work on the instance of the class, they are directly associated with the class itself.
Can we inherit one abstract class to another abstract class?
An abstract class can extend another abstract class. And any concrete subclasses must ensure that all abstract methods are implemented. Abstract classes can themselves have concrete implementations of methods. These methods are inherited just like a method in a non-abstract class.
Is it possible to inherit from multiple abstract classes in Java?
A: Because Java doesn’t support multiple inheritance. … A: Java has a rule that a class can extend only one abstract class, but can implement multiple interfaces (fully abstract classes).
Can a abstract class have constructor?
Yes! Abstract classes can have constructors! Yes, when we define a class to be an Abstract Class it cannot be instantiated but that does not mean an Abstract class cannot have a constructor. Each abstract class must have a concrete subclass which will implement the abstract methods of that abstract class.
What happens if we create object of abstract class?
you can’t create a object of abstract class because there is an abstract method which has nothing so you can call that abstract method too. If we will create an object of the abstract class and calls the method having no body(as the method is pure virtual) it will give an error.
Can we inherit abstract class?
An abstract class defines the identity of a class. An interface can inherit multiple interfaces but cannot inherit a class. An abstract class can inherit a class and multiple interfaces. … An abstract class can declare constructors and destructors.