Deck 2: Java Fundamentals

Question 1

Which of the following is not a valid Java comment?

A) /** Comment one */
B) */ Comment two /*
C) // Comment three
D) /* Comment four */

Answer 1

B

Question 2

Both character and string literals can be assigned to a char variable.

Answer 2

False

Question 3

Java is not case sensitive.

Answer 3

False

Question 4

Character literals are enclosed in __________ and string literals are enclosed in __________.

A) single quotes, double quotes
B) double quotes, single quotes
C) single quotes, single quotes
D) double quotes, double quotes

Question 5

The Java API provides a class named Math that contains numerous methods which are useful for performing complex mathematical operations.

Question 6

Programming style includes techniques for consistently putting spaces and indentation in a program to help create visual cues.

Question 7

A Java source file must be saved with the extension

A) .java
B) .javac
C) .src
D) .class

Question 8

Which of the following would contain the translated Java byte code for a program named Demo?

A) Demo.java
B) Demo.code
C) Demo.class
D) Demo.byte

Question 9

A variable's scope is the part of the program that has access to that variable.

Question 10

A Java program must have at least one of the following:

A) a comment
B) a class definition
C) a System.out.println(); statement
D) a variable declaration

Question 11

Which of the following is a named storage location in the computer's memory?

A) a literal
B) an operator
C) a constant
D) a variable

Question 12

When you call one of the Scanner class's methods to read a primitive value, such as nextInt or nextDouble, and then call the nextLine method to read a string, an annoying and hard-to-find problem can occur.

Question 13

Which of the following is a value that is written into the code of a program?

A) a literal
B) an assignment statement
C) an operator
D) a variable

Question 14

Which of the following is not a rule that must be followed when naming identifiers?

A) After the first character, you may use the letters a-z, A-Z, an underscore, a dollar sign, or the digits 0-9.
B) Identifiers can contain spaces.
C) Uppercase and lowercase characters are distinct.
D) The first character must be one of the letters a-z, A-Z, an underscore, or a dollar sign.

Question 15

To compile a program named First you would use which of the following commands?

A) java First.java
B) javac First
C) javac First.java
D) compile First.javac

Question 16

If the compiler encounters a statement that uses a variable before the variable is declared, an error will result.

Question 17

The System.out.printf method allows you to format output in a variety of ways.

Question 18

Class names and key words are examples of variables.

Question 19

A Java program will not compile unless it contains the correct line numbers.

Question 20

Named constants are initialized with a value and that value cannot change during the execution of the program.

Question 21

What is the result of the following expression?
10 + 5 * 3 - 20

A) -5
B) -50
C) 5
D) 25

Question 22

What is the value of z after the following code is executed?
int x = 5, y = 28;
Float z;
Z = (float) (y / x);

A) 5.6
B) 3.0
C) 5.0
D) 5.60

Question 23

To print "Hello, world" on the monitor, which of the following Java statements should be used?

A) System.out.println("Hello, world");
B) System Print = "Hello, world";
C) SystemOutPrintln('Hello, world');
D) system.out.println(Hello, world);

Question 24

Which Scanner class method reads a String?

A) nextLine
B) charAt
C) nextString
D) getLine

Question 25

Which of the following statements will correctly convert the data type, if x is a float and y is a double?

A) x = float y;
B) x = y;
C) x = (float)y;
D) x = y;

Question 26

What would be displayed as a result of executing the following code?
int x = 15, y = 20, z = 32;
X += 12;
Y /= 6;
Z -= 14;
System.out.println("x = " + x +
", y = " + y +
", z = " + z);

A) x = 27, y = 3.333, z = 18
B) x = 27, y = 2, z = 18
C) x = 37, y = -14, z = 4
D) x = 27, y = 3, z = 18

Question 27

Variables of the boolean data type are useful for

A) evaluating conditions that are either true or false
B) working with small integers
C) working with very large integers
D) evaluating scientific notation

Question 28

Which of the following statements is invalid?

A) double r = 9.4632E15;
B) double r = 9.4632e15;
C) double r = 2.9X106;
D) double r = 326.75;

Question 29

What would be displayed as a result of executing the following code?
final int x = 22, y = 4;
Y += x;
System.out.println("x = " + x + ", y = " + y)

A) x = 22, y = 26
B) x = 22, y = 4
C) x = 22, y = 88
D) Nothing. There is an error in the code.

Question 30

In Java, __________ must be declared before they can be used.

A) variables
B) literals
C) key words
D) comments

Question 31

What is the value of z after the following statements have been executed?
int x = 4, y = 33;
Double z;
Z = (double) (y / x);

A) 8.25
B) 4
C) 0
D) 8.0

Question 32

What output will be displayed as a result of executing the following code?
int x = 5, y = 20;
X += 32;
Y /= 4;
System.out.println("x = " + x + ", y = " + y);

A) x = 160, y = 80
B) x = 32, y = 4
C) x = 37, y = 5
D) x = 9, y = 52

Question 33

The primitive data types only allow a(n) __________ to hold a single value.

A) class
B) literal
C) object
D) variable

Question 34

In the following Java statement, what value is stored in the variable name? String name = "John Doe";

A) "name"
B) the memory address where "John Doe" is located
C) the memory address where name is located
D) John Doe

Question 35

Which of the following statements correctly creates a Scanner object for keyboard input?

A) Scanner kbd = new Scanner(System.keyboard);
B) Scanner keyboard = new Scanner(System.in);
C) Scanner keyboard(System.in);
D) Keyboard scanner = new Keyboard(System.in);

Question 36

The boolean data type may contain which of the following range of values?

A) -128 to + 127
B) true or false
C) -2,147,483,648 to +2,147,483,647
D) -32,768 to +32,767

Question 37

If the following Java statements are executed, what will be displayed? System.out.println("The top three winners are\n");
System.out.print("Jody, the Giant\n");
System.out.print("Buffy, the Barbarian");
System.out.println("Adelle, the Alligator");

A) The top three winners are
Jody, the Giant
Buffy, the Barbarian
Adelle, the Alligator
B) The top three winners are Jody, the Giant\nBuffy, the BarbarianAdelle, and the Albino
C) The top three winners are
Jody, the Giant\nBuffy, the BarbarianAdelle, the Alligator
D) The top three winners are
Jody, the Giant
Buffy, the BarbarianAdelle, the Alligator

Question 38

What is the result of the following expression?
17 % 3 * 2 - 12 + 15

A) 105
B) 12
C) 7
D) 8

Question 39

Variables are classified according to their

A) names
B) values
C) locations
D) data types

Question 40

What would be displayed as a result of executing the following code?
int x = 578;
System.out.print("There are " +
X + 5 + "\n" +
"hens in the hen house.");

A) There are 583
Hens in the hen house.
B) There are 5785
Hens in the hen house.
C) There are x5\nhens in the hen house.
D) There are 5785 hens in the hen house.

Question 41

Which of the following is not a primitive data type?

A) short
B) long
C) float
D) string

Question 42

A value that is written into the code of a program is a(n) __________.

A) literal
B) assignment statement
C) variable
D) operator

Question 43

What will be displayed as a result of executing the following code?
public class test
{
Public static void main(String[ ] args)
{
Int value1 = 9;
System.out.println(value1);
Int value2 = 45;
System.out.println(value2);
System.out.println(value3);
Value = 16;
}
}

A) 9
45
16
B) 94516
C) 9 45 16
D) Nothing. This is an error

Question 44

If x has been declared an int, which of the following statements is invalid?

A) x = 0;
B) x = -59832;
C) x = 1,000;
D) x = 592

Question 45

Every Java application program must have

A) a class named MAIN
B) a method named main
C) at least two data types
D) integer variables

Question 46

What will be displayed as a result of executing the following code? int x = 6;
String msg = "I am enjoying this class.";
String msg1 = msg.toUpperCase();
String msg2 = msg.toLowerCase();
Char ltr = msg.charAt(x);
Int strSize = msg.length();
System.out.println(msg);
System.out.println(msg1);
System.out.println(msg2);
System.out.println("Character at index x = " + ltr);
System.out.println("msg has " + strSize + "characters.");

A) I am enjoying this class.
I AM ENJOYING THIS CLASS.
I am enjoying this class.
Character at index x = e
Msg has 24 characters.
B) I am enjoying this class.
I AM ENJOYING THIS CLASS.
I am enjoying this class.
Character at index x = e
Msg has 25 characters.
C) I am enjoying this class.
I AM ENJOYING THIS CLASS.
I am enjoying this class.
Character at index x = n
Msg has 24 characters.
D) I am enjoying this class.
I AM ENJOYING THIS CLASS.
I am enjoying this class.
Character at index x = n
Msg has 25characters.

Question 47

To display the output on the next line, you can use the println method or use the __________ escape sequence in the print method.

A) \n
B) \r
C) \t
D) \b

Question 48

Which of the following is not a rule that must be followed when naming identifiers?

A) The first character must be one of the letters a-z, A-Z, and underscore or a dollar sign.
B) Identifiers can contain spaces.
C) Uppercase and lowercase characters are distinct.
D) After the first character, you may use the letters a-z, A-Z, the underscore, a dollar sign, or digits 0-9.

Question 49

Which of the following cannot be used as identifiers in Java?

A) variable names
B) class names
C) key words
D) objects

Question 50

What would be printed out as a result of the following code? System.out.println("The quick brown fox" +
"jumped over the \n"
"slow moving hen.");

A) The quick brown fox jumped over the \nslow moving hen.
B) The quick brown fox jumped over the
Slow moving hen.
C) The quick brown fox
Jumped over the
Slow moving hen.
D) Nothing - this is an error

Question 51

Which of the following is valid?

A) float y;
Y = 54.9;
B) float y;
Double z;
Z = 934.21;
Y = z;
C) float w;
W = 1.0f;
D) float v;
V = 1.0

Question 52

When the + operator is used with strings, it is known as the

A) assignment operator
B) string concatenation operator
C) addition operator
D) combines assignment operator