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Which statement is true when a superclass has protected instance variable?
Q7: Which statement is true when a superclass uses protected instance variables? A subclass object can assign an invalid value to the superclass’s instance variables, thus leaving the object in an inconsistent state.
Which of the following should be true of a superclass?
When designing a class hierarchy, which of the following should be true of a superclass? A superclass should contain the data and functionality that are common to all subclasses that inherit from the superclass. A superclass should be the largest, most complex class from which all the other subclasses are derived.
When a subclass constructor calls its superclass constructor What happens if the superclass constructor does not assign a value to an instance variable?
When a subclass constructor calls its superclass constructor, what happens if the superclass’s constructor does not assign a value to an instance variable? The program compiles and runs because the instance variables are initialized to their default values.
Which of the following in a superclass can be inherited by 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.
Is a superclass object a subclass object?
A superclass object is a subclass object. The class following the extends keyword in a class declaration is the direct superclass of the class being declared. d. Java uses interfaces to provide the benefits of multiple inheritance.
When a superclass variable refers to a subclass object and a method is called on that object the proper implementation is determined at execution time?
When a superclass variable refers to a subclass object and a method is called on that object, the proper implementation is determined at execution time. What is the process of determining the correct method to call? 1) early binding.
What are the main programming mechanisms that constitute object oriented programming?
The four principles of object-oriented programming are encapsulation, abstraction, inheritance, and polymorphism.
When designing classes which of the following would be the best reason to use inheritance?
When designing classes, which of the following would be the best reason to use inheritance? Inheritance allows you to write applications that require fewer base and super classes. Inheritance allows the creation of a subclass that can use the methods of its superclass without rewriting the code for those methods.
Which of the following would correctly invoke the constructor of a parent class?
Can a class extend itself?. 4) A sub class can inherit private members of the parent class. In Java, A subclass can, however, inherit the members of its superclass that are not private. b) true – but only when the members are superlative.
How does a subclass call the superclass constructor?
Constructors are not inherited. The superclass constructor can be called from the first line of a subclass constructor by using the keyword super and passing appropriate parameters to set the private instance variables of the superclass.
Which of the following is the superclass constructor call syntax quizlet?
Which of the following is the superclass constructor call syntax? keyword super, followed by a dot (.) . keyword super, followed by a set of parentheses containing the superclass constructor arguments.
Which of the following statement is true about super keyword?
0 super keyword is used to invoke immediate parent class method All the given options are correct super() is used to invoke immediate parent class constructor . super() should be the first statement in the * CV.
Which Cannot be inherited from a superclass?
5 Answers. Constructors, static initializers, and instance initializers are not members and therefore are not inherited.
What does a subclass inherit from a superclass choose all that apply?
What does a subclass inherit from its superclass? It inherits all the superclass’s attributes.
Which of the following would be a superclass of employee?
Which should be the superclass and which should be the subclass? What are the inheritance relationships between classes BankAccount, CheckingAccount, and SavingsAccount? Therefore, the CheckingAccount and SavingsAccount classes inherit from the more general BankAcccount class. Consider the method doSomething(Car c).
Is superclass instance of subclass?
When one class inherits from another class in Java, the two classes take on certain roles. The class that extends (inherits from another class) is the subclass and the class that is being extended (the class being inherited from) is the superclass . In other words, the subclass extends the superclass.
How a superclass variable can reference a subclass object?
First approach (Referencing using Superclass reference): A reference variable of a superclass can be used to a refer any subclass object derived from that superclass. If the methods are present in SuperClass, but overridden by SubClass, it will be the overridden method that will be executed.
What would a superclass contain?
A superclass is the class from which many subclasses can be created. The subclasses inherit the characteristics of a superclass. The superclass is also known as the parent class or base class.
Which statement below about abstract classes is true?
Discuss it A Declaring it abstract using the virtual keyword B Making at least one member function as virtual function C Making at least one member function as pure virtual function D Making all member function const.
Which statement accurately describes an abstract class?
1. Which among the following best describes abstract classes? Explanation: The condition for a class to be called abstract class is that it must have at least one pure virtual function. The keyword abstract must be used while defining abstract class in java.
Which of the following is correct about interface?
Which of the following statements is correct about an interface? 1) An interface can be implemented by multiple classes in the same program. 3) The functions declared in an interface have a body 4) A class that implements an interface can explicitly implement members of that interface. 5) NULL.
How is polymorphism achieved?
The compile time polymorphism can be achieved by function overloading or by operator overloading. The overloaded functions are invoked by matching the type and number of arguments and this is done at the compile time so, compiler selects the appropriate function at the compile time.
What kind of performance can you expect if you perform linear search on a sorted array?
What kind of performance can you expect if you perform linear search on a sorted array? (Linear search doesn’t make any assumptions about whether or not its data is sorted. So, if the data happens to be sorted or not, it won’t make any difference.
Can a program exhibit dynamic polymorphism if it only implements early binding?
Can a program exhibit polymorphism if it only implements early binding? Yes, because one form of polymorphism is overloading. While inheritance and interfaces support polymorphism, they only do so if one has late binding.
