Java Quizs Question & Answers – Character and Boolean Data Types

Q 1. What will be the output of the following Java program?

class mainclass {

public static void main(String args[])

{

char a = ‘A’;

a++;

System.out.print((int)a);

}

}

A. 64
B. 65
C. 67
D. 66

Show Answer

Answer:-D. 66

Explanation

ASCII value of ‘A’ is 65, on using ++ operator character value increments by one. output:$ javac mainclass.java $ java mainclass 66

Q 2. What will be the output of the following Java program?

class mainclass {

public static void main(String args[])

{

boolean var1 = true;

boolean var2 = false;

if (var1)

System.out.println(var1);

else

System.out.println(var2);

}

}

A. 0
B. 1
C. true
D. false

Show Answer

Answer:-C. true

Explanation

None. output:$ javac mainclass.java $ java mainclass true

Q 3. What will be the output of the following Java code?

class booloperators {

public static void main(String args[])

{

boolean var1 = true;

boolean var2 = false;

System.out.println((var1 & var2));

}

}

A. 0
B. 1
C. true
D. false

Show Answer

Answer:-D. false

Explanation

boolean ‘&’ operator always returns true or false. It returns true when both the values are true and false otherwise. Since, var1 is defined true and var2 is defined false hence their ‘&’ operator result is false. output:$ javac booloperators.java $ java booloperators false

Q 4. What will be the output of the following Java code?

class asciicodes {

public static void main(String args[]

{

char var1 = ‘A’;

char var2 = ‘a’;

System.out.println((int)var1 + ” ” + (int)var2);

}

}

A. 162
B. 67 95
C. 65 97
D. 66 98

Show Answer

Answer:-C. 65 97

Explanation

ASCII code for ‘A’ is 65 and for ‘a’ is 97. output:$ javac asciicodes.java $ java asciicodes 65 97

Q 5. What is the numerical range of a char data type in Java?
A. -128 to 127
B. 0 to 256
C. 0 to 32767
D. 0 to 65535

Show Answer

Answer:-D. 0 to 65535

Explanation

Char occupies 16-bit in memory, so it supports 216 i:e from 0 to 65535.

Q 6. Which of these coding types is used for data type characters in Java?
A. ASCII
B. ISO-LATIN-1
C. UNICODE
D. None of the mentioned

Show Answer

Answer:-C. UNICODE

Explanation

Unicode defines fully international character set that can represent all the characters found in all human languages. Its range is from 0 to 65536.

Q 7. Which of these values can a boolean variable contain?
A. True & False
B. 0 & 1
C. Any integer value
D. true

Show Answer

Answer:-A. True & False

Explanation

Boolean variable can contain only one of two possible values, true and false.

Q 8. Which of these occupy first 0 to 127 in Unicode character set used for characters in Java?
A. ASCII
B. ISO-LATIN-1
C. None of the mentioned
D. ASCII and ISO-LATIN1

Show Answer

Answer:-D. ASCII and ISO-LATIN1

Explanation

First 0 to 127 character set in Unicode are same as those of ISO-LATIN-1 and ASCII.

Q 9. Which one is a valid declaration of a boolean?
A. boolean b1 = 1;
B. boolean b2 = ‘false’;
C. boolean b3 = false;
D. boolean b4 = ‘true’

Show Answer

Answer:-C. boolean b3 = false;

Explanation

Boolean can only be assigned true or false literals.

Q 10. What will be the output of the following Java program?

class array_output {

public static void main(String args[])

{

char array_variable [] = new char[10];

for (int i = 0; i < 10; ++i) {

sarray_variable[i] = ‘i’;

System.out.print(array_variable[i] + “” );

i++;

}

}

}

A. i i i i i
B. 0 1 2 3 4
C. i j k l m
D. None of the mentioned

Show Answer

Answer:-A. i i i i i

Explanation

output:$ javac array_output.java $ java array_output i i i i i

Q 11. What is the size of a char data type in Java?

A. 8-bit

B. 16-bit

C. 32-bit

D. 64-bit

Show Answer

Answer:-B. 16-bit

Q 12. Which character set does Java use to represent the char data type?

A. ASCII

B. Extended ASCII

C. Unicode (UTF-16)

D. ISO-8859-1

Show Answer

Answer:-C. Unicode (UTF-16)

Q 13. What is the default value of a boolean variable when declared as a class member?

A. true

B. false

C. null

D. 0

Show Answer

Answer:-B. false

Q 14. What is the range of the char data type in Java?

A. -128 to 127

B. 0 to 255

C. 0 to 65,535

D. -32,768 to 32,767

Show Answer

Answer:-C. 0 to 65,535

Q 15. Which of the following is a valid way to initialize a char?

A. char c = "A";

B. char c = 'Ab';

C. char c = 65;

D. char c = A;

Show Answer

Answer:-C. char c = 65;

Q 16. What will be the output of: boolean b = 1;?

A. true

B. false

C. Compilation Error

D. Runtime Error

Show Answer

Answer:-C. Compilation Error

Q 17. Which escape sequence represents a “tab” in a char literal?

A. \t

B. \b

C. \n

D. \r

Show Answer

Answer:-A. \t

Q 18. What is the numerical value of the Unicode character \u0000?

A. 1

B. 0

C. 65

D. 255

Show Answer

Answer:-B. 0

Q 19. Which of these operators can be used with boolean variables?

A. +

B. *

C. &

D. <<

Show Answer

Answer:-C. &

Q 20. Can you perform arithmetic operations on a char variable?

A. Yes, because it is treated as an unsigned 16-bit integer.

B. No, it is purely for text.

C. Yes, but only with other char variables.

D. No, Java throws a ClassCastException.

Show Answer

Answer:-A. Yes, because it is treated as an unsigned 16-bit integer.

Q 21. What is the output of: System.out.println('A' + 1);?

A. B

B. A1

C. 66

D. Compilation Error

Show Answer

Answer:-C. 66

Q 22. Which of these is a valid boolean literal?

A. TRUE

B. 0

C. false

D. (boolean)1

Show Answer

Answer:-C. false

Q 23. What is the result of true && false?

A. true

B. false

C. null

D. 1

Show Answer

Answer:-B. false

Q 24. How do you represent the single quote character as a char literal?

A. '''

B. '\''

C. "'"

D. \quote

Show Answer

Answer:-B. ‘\”

Q 25. If char c = 'A';, what does (int)c return?

A. 1

B. 0

C. 65

D. 97

Show Answer

Answer:-C. 65

Q 26. What is the size of a boolean in Java?

A. Exactly 1 bit.

B. Exactly 8 bits.

C. It is virtual machine dependent (not precisely defined).

D. 16 bits.

Show Answer

Answer:-C. It is virtual machine dependent (not precisely defined).

Q 27. Which of the following is NOT a valid char?

A. char c = '\u0041';

B. char c = 0xbeef;

C. char c = -1;

D. char c = '\n';

Show Answer

Answer:-C. char c = -1;

Q 28. What is the output of System.out.println(10 > 9);?

A. 1

B. true

C. false

D. 10 > 9

Show Answer

Answer:-B. true

Q 29. Can a boolean be cast to an int in Java?

A. Yes, true becomes 1.

B. Yes, but only explicitly: (int)true.

C. No, boolean and int are incompatible types.

D. Only in Java 8 and above.

Show Answer

Answer:-C. No, boolean and int are incompatible types.

Q 30. What is the wrapper class for char and boolean respectively?

A. Char, Bool

B. Character, Boolean

C. String, Boolean

D. character, boolean

Show Answer

Answer:-B. Character, Boolean