All Flashcards
What is the definition of 'Superclass'?
A class from which other classes (subclasses) inherit attributes and methods.
What is the definition of 'Subclass'?
A class that inherits attributes and methods from another class (superclass).
What is the definition of the 'super' keyword?
A keyword used to call the superclass's constructor or access its members from the subclass.
What is the definition of 'Constructor'?
A special method used to initialize objects of a class.
What is the definition of 'Inheritance'?
A mechanism where a class acquires the properties (attributes and methods) of another class.
What is the definition of 'No-argument constructor'?
A constructor that takes no arguments.
What is the definition of 'Explicit constructor call'?
A constructor call made directly in the code, using the 'super' keyword.
What is the definition of 'Implicit constructor call'?
A constructor call automatically inserted by the compiler when no explicit call is made.
What is the definition of 'Object class'?
The ultimate superclass of all classes in Java.
What is the definition of 'Instance variable'?
A variable defined in a class (i.e., a member variable) for which every object of the class has its own copy.
Why are constructors not inherited?
Constructors are specific to the class they are defined in and are responsible for initializing objects of that class.
What is the purpose of the 'super' keyword in a subclass constructor?
To call the constructor of the superclass, allowing reuse of initialization logic.
What happens if a subclass constructor doesn't explicitly call a superclass constructor?
Java automatically inserts a call to the superclass's no-argument constructor.
Why is it important to call the superclass constructor in a subclass?
To ensure that the superclass's instance variables are properly initialized.
Explain the constructor call chain in Java.
Subclass constructor calls superclass constructor, which may call its superclass constructor, and so on, up to the Object class constructor.
What is the role of the Object class in the constructor call chain?
It is the ultimate superclass, and its constructor is always the first to be called.
How does the 'super' keyword promote code reuse?
It allows subclasses to leverage the initialization logic already defined in the superclass constructor.
What is the significance of calling 'super' as the first statement in a subclass constructor?
It ensures that the superclass is initialized before any subclass-specific initialization takes place.
Explain how instance variables are initialized in a subclass when using 'super'.
Instance variables of the superclass are initialized by the superclass constructor, and subclass-specific instance variables are initialized separately in the subclass constructor.
What is the impact of not properly initializing the superclass when creating a subclass?
It can lead to unexpected behavior or errors due to uninitialized or incorrectly initialized superclass members.
How is the concept of calling superclass constructors applied in GUI frameworks?
When creating custom UI components, subclasses call the superclass constructor to initialize basic properties like size and position.
How is 'super' used in inheritance hierarchies for database entities?
Subclasses representing specific entity types call the superclass constructor to initialize common fields like ID and creation date.
How is the concept of calling superclass constructors applied when extending exception classes?
Custom exception classes call the superclass constructor to set the error message and other relevant information.
How is 'super' used when creating specialized data structures?
Subclasses of generic data structures (e.g., lists, trees) use 'super' to initialize the underlying data storage.
How is the concept of calling superclass constructors applied in game development?
When creating different types of game objects, subclasses call the superclass constructor to initialize common properties like position, health, and damage.
How is 'super' used in frameworks that implement design patterns like Template Method?
Subclasses call the superclass constructor to set up the basic structure of the algorithm, then implement specific steps in their own methods.
How is the concept of calling superclass constructors applied in web frameworks?
When creating custom controllers or models, subclasses call the superclass constructor to initialize framework-specific dependencies and configurations.
How is 'super' used in systems with plugin architectures?
Plugin classes call the superclass constructor to register themselves with the system and access core functionalities.
How is the concept of calling superclass constructors applied in scientific simulations?
When creating specialized simulation objects, subclasses call the superclass constructor to initialize common physical properties and simulation parameters.
How is 'super' used in embedded systems programming?
Subclasses representing specific hardware components call the superclass constructor to initialize device drivers and communication protocols.