Deck 2: Basic Elements of Java

Question 1

The null string contains only the blank character.

Answer 1

False

Question 2

The symbol '5' does not belong to the char data type because 5 is a digit.

Answer 2

False

Question 3

Suppose x = 18.6. The output of the statement System.out.println((int)(x) / 3); is 6.

Answer 3

True

Question 4

Suppose that index is an int variable. The statement index = index + 1; is equivalent to index++;

Question 5

The == characters are a special symbol in Java.

Question 6

A value such as 'd' is called a character constant.

Question 7

The pair of characters // is used for single line comments.

Question 8

Suppose console is a Scanner object initialized with the standard input device. The expression console.nextInt(); is used to read one int value and the expression console.nextDouble(); is used to read two int values.

Question 9

An operator that has only one operand is called a unique operator.

Question 10

Suppose console is a Scanner object initialized with the standard input device and feet and inches are int variables. Consider the following statements: feet = console.nextInt(); inches = console.nextInt(); These statements require the value of feet and inches to be input on separate lines.

Question 11

When a value of one data type is automatically changed to another data type, an implicit type coercion has occurred.

Question 12

When evaluating a mixed expression, all integer operands are converted to floating-point numbers with the decimal part of zero.

Question 13

Java automatically initializes all variables.

Question 14

The number of significant digits in a double variable is up to 15.

Question 15

If a = 4; and b = 3;, then after the statement a = b; executes, the value of b is 4 and the value of a is 3.

Question 16

The Java language is strongly typed.

Question 17

The data type float is a floating-point data type.

Question 18

An identifier can be any sequence of characters and integers.

Question 19

Operators of the same precedence are evaluated from right to left.

Question 20

The value of a variable may change during program execution.

Question 21

Operators that have two operands are called ____.

A) unary operators
C) operators
B) binary operators
D) expressions

Question 22

Which of the following statements about a named constant is NOT true?

A) Its content cannot change during program execution.
B) Its value can be changed during program execution.
C) It is a memory location.
D) It is declared using the reserved word final.

Question 23

The length of the string "first java program" is:

A) 16
C) 19
B) 18
D) 20

Question 24

Which of the following is a valid int value?

A) 3279
C) 3270.00
B) 3,279
D) -922337203684547758808

Question 25

Suppose x = 8. After the execution of the statement y = x++; y is 8 and x is 10.

Question 26

In Java, a period is used to terminate a statement.

Question 27

The ____ rules of a programming language tell you which statements are legal, or accepted by the programming language.

A) semantic
C) syntax
B) logical
D) grammatical

Question 28

If ++x is used in an expression, first the expression is evaluated, and then the value of x is incremented by 1.

Question 29

The value of the expression 14 % 3 is ____.

A) 1
C) 3
B) 2
D) 4

Question 30

The character sequence \n moves the insertion point at the end of the current line.

Question 31

Both System.out.println and System.out.print can be used to output a string on the standard output device.

Question 32

The value of the expression 5 + 10 % 4 - 3 is ____.

A) 0
C) 4
B) 2
D) 5

Question 33

Which of the following is a valid char value?

A) '$_'
C) 'n\'
B) '%'
D) "a"

Question 34

The expression (double)(5 + 4) evaluates to ____.

A) 8
C) 9.0
B) 9
D) 10.0

Question 35

What type of Java statement(s) stores a value in a variable?

A) input
B) output
C) assignment
D) Both an input statement and an assignment statement

Question 36

Which of the following is a valid Java identifier?

A) $pay
C) newGrade!
B) 4myGrade!
D) 1dollar

Question 37

Suppose that x and y are int variables and x = 7 and y = 8. After the statement: x = x * y - 2; executes, the value of x is ____.

A) 42
C) 56
B) 54
D) 58

Question 38

The memory allocated for a double value is ____ bytes.

A) 2
C) 8
B) 4
D) 16

Question 39

Which of the following is NOT a reserved word in Java?

A) double
C) static
B) throws
D) num

Question 40

The expression (int)8.7 evaluates to ____.

A) 8
C) 9.0
B) 8.0
D) 9

Question 41

____ are executable statements that inform the user what to do.

A) Variables
C) Named constants
B) Prompt lines
D) Expressions

Question 42

Consider the following program. // Insertion Point 1 public class CircleArea {// Insertion Point 2 static final float PI = 3.14 public static void main(String[]args) {//Insertion Point 3 float r = 2.0; float area; area = PI * r * r; System.out.println("Area = " + area);} // Insertion Point 4} In the above code, where do the import statements belong?

A) Insertion Point 1
C) Insertion Point 3
B) Insertion Point 2
D) Insertion Point 4

Question 43

Which of the following is the newline character?

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

Question 44

Given char ch; int num; double pay; Which of the following assignment statements are valid? (i) ch = '*'; (ii) pay = num * pay; (iii) rate * 40 = pay;

A) Only (i) is valid
C) (ii) and (iii) are valid
B) (i) and (ii) are valid
D) (i) and (iii) are valid

Question 45

The declaration int a, b, c; is equivalent to which of the following?

A) int a , b c;
C) int abc;
B) int a;
D) int a b c;

Question 46

Suppose x = 4 and y = 2. If the statement x *= y; is executed once, what is the value of x?

A) 2
C) 8
B) 4
D) This is an illegal statement in Java.

Question 47

What is the output of the following statement? System.out.println("Welcome \n Home");

A) WelcomeHome
B) Welcome Home
C) Welcome
D) Welcome \n Home

Question 48

The standard output object in Java is ____.

A) output
C) Sys.out
B) System.out
D) System.in

Question 49

Suppose that alpha and beta are int variables. The statement alpha = --beta; is equivalent to the statement(s) ____.

A) beta = beta - 1;
C) beta = beta - 1;
B) beta = beta - 1;
D) alpha = beta;

Question 50

Consider the following program. public class CircleArea {static Scanner console = new Scanner(System.in); static final float PI = 3.14; public static void main(String[]args) {float r; float area; r = console.nextDouble(); area = PI * r * r; System.out.println("Area = " + area);}} To successfully compile this program, which of the following import statement is required?

A) import java.io;
C) import java.lang;
B) import java.util;
D) No import statement is required