- Which is better abstract class or interface?
- Can we extend abstract class?
- Is it possible to create constructor in an abstract class?
- How do you call a constructor from an abstract class?
- Can you initialize an abstract class C#?
- Can an interface have a constructor?
- Can abstract class have method body?
- Can we inherit abstract class?
Which is better abstract class or interface?
The short answer: An abstract class allows you to create functionality that subclasses can implement or override.
An interface only allows you to define functionality, not implement it.
And whereas a class can extend only one abstract class, it can take advantage of multiple interfaces..
Can we extend abstract class?
Abstract classes are similar to interfaces. You cannot instantiate them, and they may contain a mix of methods declared with or without an implementation. … In addition, you can extend only one class, whether or not it is abstract, whereas you can implement any number of interfaces.
Is it possible to create constructor in an abstract class?
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.
How do you call a constructor from an abstract class?
You can’t call an abstract class constructor with a class instance creation expression, i.e. As constructors of abstract classes can only be called within subclass constructors (and by chaining one to another within the same class), I typically make them protected … making them public would serve no purpose.
Can you initialize an abstract class C#?
an abstract class can have member variables that needs to be initialized,so they can be initialized in the abstract class constructor and this constructor is called when derived class object is initialized. Constructors on abstract types can be called only by derived types.
Can an interface have a constructor?
No, you cannot have a constructor within an interface in Java. You can have only public, static, final variables and, public, abstract, methods as of Java7. From Java8 onwards interfaces allow default methods and static methods.
Can abstract class have method body?
Abstract methods cannot have a body; all they can have is a method signature as shown in the example above. Variables are not allowed in interface. Hence any data declaration is ‘ public static final ‘; hence only constants. Interfaces can extend other interfaces ( one or more ) but not classes ( abstract or not ).
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.