Deck 2: Introduction to Java Applications; Inputoutput and Operators

Question 1

Which of the following escape sequences represents a carriage return?

A) \n.
B) \r.
C) \cr.
D) \c.

Answer 1

B

Question 2

Which of the following is the escape character?

A) *
B) \
C) \n
D) "

Answer 2

B

Question 3

Which of the following does not contain a syntax error?

A) System.out.println('Hello world!'):
B) System.out.println("Hello world!");
C) System.out.println("Hello world!");
D) System.out.println(Hello world!);

Answer 3

C

Question 4

Which of the following statement displays Hello World?

A) System.out.printf("%2s", "Hello " "World");
B) System.out.printf("%s %s", "Hello", "World");
C) System.out.printf("%s%s", "Hello, World");
D) System.out.printf("s% s%", "Hello", "World");

Question 5

Which of the following is not a Java primitive type?

A) char
B) byte
C) real
D) double

Question 6

Which of the following cannot cause a syntax error to be reported by the Java compiler?

A) Mismatched {}
B) Missing */ in a comment that begins with /*
C) Missing ;
D) An extra blank line.

Question 7

Java's predefined classes are grouped into

A) packets.
B) declarations.
C) Galleries.
D) packages.

Question 8

Which is the output of the following statements? System.out.print("Hello ");
System.out.println("World");

A) Hello World
B) HelloWorld
C) Hello World
D) World Hello

Question 9

Which command compiles the Java source code file Welcome.java?

A) cd Welcome.java
B) javac Welcome.java
C) java Welcome.java
D) compile Welcome.java

Question 10

Which command executes the Java class file Welcome.class?

A) java welcome
B) java Welcome.class
C) java Welcome
D) run Welcome.class

Question 11

Which of the following is not a valid Java identifier?

A) my Value
B) $_AAA1
C) width
D) m_x

Question 12

import declarations must be placed

A) inside the class declaration's body.
B) before the class declaration.
C) after the class declaration.
D) all of the above will work.

Question 13

Which of the following statements is true?

A) System.out.print("Enter your age: "); prompts the user to take action.
B) Class names typically begin with a capital letter.
C) Package java.lang is imported in every Java program.
D) All of the above are true.

Question 14

Programs remember numbers and other data in the computer's memory and access that data through program elements called

A) comments.
B) messages.
C) integers.
D) variables.

Question 15

________ enables a program to read data from the user.

A) printf.
B) import declaration.
C) Scanner.
D) main.

Question 16

Which of the following is a variable declaration statement?

A) int total;
B) import java.util.Scanner;
C) public static void main(String args[])
D) // first string entered by user

Question 17

method printf requires multiple arguments, the arguments are separated with ________.

A) colons (:).
B) semicolons (;).
C) commas (,).
D) periods (.).

Question 18

Which of the following statements will print a single line containing "hello there"?

A) System.out.println("hello"); System.out.println(" there");
B) System.out.println("hello" , " there");
C) System.out.println("hello"); System.out.print(" there");
D) System.out.print("hello"); System.out.println(" there");

Question 19

Which of the following statements would display the phase Java is fun?

A) System.out.println("hellois fun\rJava ");
B) System.out.println('Java is fun');
C) System.out.println("\"Java is fun\"");
D) System.out.println(Java is fun);

Question 20

End-of-line comments that should be ignored by the compiler are denoted using

A) Two forward slashes (//).
B) Three forward slashes (///).
C) A slash and a star (/*).
D) A slash and two stars (/**).

Question 21

Which of the following statements is false?

A) Primitive types are keywords.
B) Primitive types must appear in all lowercase letters.
C) Real numbers contain decimal points.
D) Variable name identifiers must begin with a lowercase letter.

Question 22

of the following is a relational or equality operator except:

A) <=
B) =!
C) ==
D) >

Question 23

will be output after the following Java statements have been executed (assume all variables are of type int)? a = 4;
B = 12;
C = 37;
D = 51;
If (a < b) {
System.out.println("a < b");
}
If (a > b) {
System.out.println("a > b");
}
If (d <= c) {
System.out.println("d <= c");
}
If (c != d) {
System.out.println("c != d");
}

A) a < b c != d
B) a < b d <= c
C != d
C) a > b c != d
D) a < b c < d
A != b

Question 24

Optional parentheses in expressions are said to be

A) redundant.
B) binary operators.
C) implied.
D) declared.

Question 25

Which of the following is a Scanner method for inputting an integer value?

A) nextInteger
B) integer
C) nextInt
D) int

Question 26

Given the Java statement int number1 = input.nextInt();
In which input is a Scanner, which of the following occurs if the user does not enter a valid int value?

A) A compilation error occurs.
B) The program continues executing and assigns the value 0 to number1.
C) A runtime logic error occurs.
D) None of the above.

Question 27

Portions of statements that contain calculations are called

A) variables.
B) constants.
C) expressions.
D) None of the above.

Question 28

Which of the following is not an arithmetic operator?

A) +
B) -
C) .
D) %

Question 29

Given the Java statement int sum = number1 + number2;
Which of the following statements is false?

A) It's an assignment statement.
B) It calculates the sum of variables number1 and number2.
C) The operands of the addition operator are number1 and number2.
D) It assigns the value of number1 to sum.

Question 30

is the value of result after the following Java statements execute (assume all variables are of type int)? a = 4;
B = 12;
C = 37;
D = 51;
Result = d % a * c + a % b + a;

A) 119
B) 51
C) 127
D) 59

Question 31

Which of the following is not a compilation error?

A) Neglecting to initialize a local variable in a method before it is used.
B) Placing a semicolon at the end of the first line of an if statement.
C) Omitting the left and right parenthesis for the condition of an if statement.
D) All are compilation errors.

Question 32

Which of the following statements does not alter the value stored in a memory location?

A) int a;
B) number = 12;
C) y = y + 2;
D) width = Integer.parseInt(input);

Question 33

format specifier ________ is a placeholder for an int value.

A) %n
B) %d
C) %int
D) %s