AP CSA Unit 2 Test review

Match the following

• (int) (Math.random() * 11 + 1)

• Integer 0-10, inclusive

• (int) (Math.random() * 20)

• Integer 1-11, inclusive

•  (Math.random()*10)

• Integer 0-99, inclusive

• (int) (Math.random()*100)

• Integer 0-19, inclusive

• (int) (Math.random() * 11)

• 0.0 <= x < 10.0

Consider the following code segment.

What is printed when the code segment is executed?

• 2

  5

  -1

• 2

  5

  2

• 2

  6

  -1

• 3

  6

  -1

• -1

  -1

  2

The code segment below is intended to randomly print one of the values 2, 4, 6, or 8 with equal probability.

Which of the following can be used to replace /* missing code */ so that the code segment works as intended?

• Math.random() * 4 + 1

• Math.random() * 8

• (int) (Math.random() * 4)

• (int) (Math.random() * 4 + 1)

• (int) (Math.random() * 8 + 1)

Consider the following code segment, which is intended to display 6.0.

Which of the following best describes the error, if any, in the code segment?

• There are no errors and the code works as intended.

• Either the numerator or the denominator of the fraction 1 / 2 should be cast as double.

• The expression fact1 * fact 2 should be cast as double.

• The expressions 1 / 2 and 3 * 4 should both be cast as double.

• The variables fact1 and fact2 should both be declared as int.

String txt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

What is the correct way to find the length of "txt" string?

• int len = length(txt);

• float len = txt.length();

• int len = txt.length();

• double len = length(txt);

System.out.println(1 + 2 + "3");

• 123

• 6

• 33

• error

A standard way of visualizing the design of a program that displays class names, attributes, behaviors, and relationships to other classes is known as a(n):

• Program Design Layout

• Abstraction Model

• UML Diagram

• Class Hierarchy

The object-oriented programming concept where the instance variables of a class are hidden from other classes and can be accessed only through the methods of the class is called:

• Abstraction

• Inheritance

• Polymorphism

• Encapsulation

A variable defined in a class that represents an attribute of an object is referred to as a(n):

• Local variable

• Reference type

• Primitive type

• Instance variable

The first line of a constructor, which includes the public keyword, the constructor name, and any parameters, is called the:

• Class Definition

• Method Header

• Constructor signature

• Formal parameter line