Questions
5 of 13
Can an Interface have a Constructor?
Difficulty: 2/10
Constructors and Interfaces
No, an interface does not have a constructor in Java or C#. A constructor initializes an instance of a concrete class, while an interface is a contract and cannot normally be instantiated directly. The implementing class owns object construction and is responsible for initializing its state. This distinction reinforces the separation between an abstraction's contract and the concrete object's lifecycle.
javascript
- 1
Interfaces cannot normally be instantiated.
- 2
Therefore, they do not have object constructors.
- 3
Implementing classes define constructors.
- 4
Dependency initialization can be performed in the implementing class.
- 5
Interface default/static methods do not change the basic role of constructors.
Follow-up Questions
- Why can't interfaces be instantiated?
- Can an abstract class have a constructor?
- How does dependency injection initialize an interface dependency?
- Can an interface have static initialization?