Flow of Control
Arrays
Inheritance & Abstract Classes
Keywords & Modifiers
Programming
100
How many times does the body of this while loop execute?
int x = 0;
while (x / 3 < 3)
{
x++;
}
9
100
What code declares a two-dimensional array of doubles named "hours" with 10 rows and 7 columns?
double[][] hours = new double[10][7];
100
The extends keyword applies to...
a class inheriting from another class; defines a child class from its parent.
100
What does the "final" keyword indicate?
This field/class cannot be modified.
100
A class called Quiz has a method with the following signature:
public static void displayStats(int numGrades)
How would you call the displayStats method?
Quiz.displayStats(25);
200
How many iterations does the following loop encounter?
7
200
When referring to arrays, what is an element?
The value at a certain position in the array.
200
How do you instantiate an object from an abstract class?
You can't- at least not directly.
200
To which classes does the protected keyword grant access?
The class itself, any subclasses, and any classes in the same package.
200
We have used the following constant a couple of times in this course:
Integer.MAX_VALUE
What kind of value is this?
class variable; a public constant in the Integer class
300
What output is produced by the following code?
Hello
Hello
300
Given the following two-dimensional array declaration:
double[][] grades = new double[30][10];
What will the following code output?
System.out.println(grades.length);
30
300
What fields and methods are inherited by a subclass?
(Hint: access modifiers?)
Protected and public
300
Which keyword(s) is/are used when a variable belongs to the entire class?
static
300
Given the following code:
How would you call the power method to calculate 3^5 (3 to the 5th power) and set it to an integer variable named 'number'?
int number = Calc.power(3, 5);
400
What output is produced by the following code?
0
count after loop = 1
400
Given the following array, what would the values in numbers be changed to after only one pass of selection sort?
int[] numbers = {6. 3, 4, 7, 9, 2, 5};
{2, 3, 4, 7, 9, 6, 5}
400
In object-oriented programming (OOP), what is the principle of overriding?
A method from a parent class with the same signature (name, parameters, return type) is redefined by a child class.
400
What code would declare and initialize a constant called SIZE to represent the value 30 for the length of an array?
public static final int SIZE = 30;
400
What is the purpose of a parameterized constructor?
To instantiate a new object by initializing its instance variables with the given arguments.
500
What output is produced by the following statements?
Positive
-100
500
What code will declare (and initialize) a two-dimensional array named "settings" with the same layout as the table of data below?
int[][] settings = { {12, 24, 32, 21}, {14, 67, 87, 65},{19, 1, 24, 12} };
500
Which of the following are properties of an abstract class?
A) An abstract class cannot have instance variables and methods.
B) An abstract class can have instance variables and methods.
C) An abstract class is used for inheritance purposes
D) An abstract class cannot be instantiated.
E) There is no public constructor provided by an abstract class.
F) The constructor should initialize all instance variables.
B) An abstract class can have instance variables and methods.
C) An abstract class is used for inheritance purposes
D) An abstract class cannot be instantiated.
E) There is no public constructor provided by an abstract class.
500
The extends keyword applies to:
1) a member variable
2) a method of the class
3) an expression
4) a class inheriting from another class
5) the overridden toString method
4
500
What is the correct implementation of the equals method of the following class?
