Quiz 3
Question 1
How is the inheritance relationship represented in a UML diagram?
By an arrow pointing from the derived class to the base class.
Question 2
Assume that Mammal is a subclass of Animal and Dog is a subclass of Mammal.
Given the following declarations:
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Animal animal;
Mammal mammal;
Dog dog;
Which of the follow statements is not legal?
Question 3
Given the following base case constructor definition:
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public QuizQuestion(int initialPoints)
{
points = initialPoints;
}
How would this constructor be called from a derived class constructor?
Question 4
What is the difference between overriding a method and overloading a method?
A method in a derived class overrides a method with the same signature in the base class. A new method with a different signature but same name overloads an existing method in the same class.
Question 5
Given the following code:
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public class Larry
{
private Curly curly;
/* additional instance variables and methods */
}
public class Moe extends Larry
{
/* instance variables and methods */
}
Which of the following best describes the relationship between Larry, Curly, and Moe?
Larry has-a Curly. Moe is-a Larry.
Question 6
The keyword super can be used to call an overridden base class method in a method of the derived class.
True
Question 7
Why is it a good idea to override the toString and equals methods when creating a new class?
The inherited versions will not handle any private instance variables of the new class.
Question 8
Which of the following best describes the concept of inheritance?
A derived class inherits public methods from a base class.
Question 9
The Object class is the ultimate ancestor of every other class.
True
Question 10
What is the result if the final modifier is used in the heading of a method definition?
The method can not be overridden.
Question 11
A private method in a base class is inherited by a derived class.
False
Question 12
A method in a derived class with the same signature overrides the method from the base class.
True