No, abstract classes cannot be instantiated. There are two reasons: to enforce abstract methods and ensure conceptual integrity.
Can abstract classes be instantiated in Java?
No, abstract classes cannot be instantiated.
Reason:
An abstract class is a special type of class that contains abstract methods, that is, functions that are not implemented. An abstract method declares the method name, parameter list, and return type, but no actual implementation code.
Since an abstract class contains abstract methods, its instance cannot be created. This means that you cannot use the new
keyword to instantiate an abstract class.
Why not use abstract classes?
There are two reasons not to use abstract class instantiation:
- Forcing implementation of abstract methods: The purpose of an abstract class is to force subclasses to implement it abstract method. If an abstract class can be instantiated, then subclasses can bypass implementing abstract methods.
-
Ensure conceptual integrity: Abstract classes represent concepts that are not suitable for instantiation. For example, an
Animal
abstract class can define the general characteristics of animals, but it cannot be instantiated into a specific animal.
Alternative:
If you need a type that cannot be instantiated, you can use Interface. An interface is similar to an abstract class, but it only contains abstract methods and no concrete implementations. Subclasses must implement these abstract methods to use the interface.
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