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Can a subclass call another subclass?
A class in Java can be declared as a subclass of another class using the extends keyword. A subclass inherits variables and methods from its superclass and can use them as if they were declared within the subclass itself: A subclass can be further subclassed.
Can a subclass reference refer to a superclass object?
No. It makes zero sense to allow that. The reason is because subclasses generally define additional behavior. If you could assign a superclass object to a subclass reference, you would run into problems at runtime when you try to access class members that don’t actually exist.
Can a subclass inherit from a subclass?
A subclass inherits all the members (fields, methods, and nested classes) from its superclass. Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass.
Can an object subclass another object?
2. Can an object be a subclass of another object? A. Yes—as long as single inheritance is followed.
Can a subclass have its own constructor?
A class that extends another class does not inherit its constructors. However, the subclass must call a constructor in the superclass inside of its the subclass constructors! If a subclass calls another constructor within itself, then the called constructor must call the superclass constructor.
Can a superclass access subclass member?
Does a superclass have access to the members of a subclass? No, a superclass has no knowledge of its subclasses. Yes, a subclass has access to all nonprivate members of its superclass.
How do you define a subclass?
Definition: A subclass is a class that derives from another class. A subclass inherits state and behavior from all of its ancestors. The term superclass refers to a class’s direct ancestor as well as all of its ascendant classes.
Does subclass call superclass constructor?
Subclass Constructors Because a constructor initializes an instance of a class, they are never inherited; however, the subclass must call a superclass constructor as it is an extension of a superclass object.
Does a subclass need to have a constructor quizlet?
Does a Subclass need to have a constructor? Yes, the subclass has its own constructor, either explicit or implicitly created. How does a Subclass call the Superclass constructor? Using the super keyword in the first line of the subclass constructor.