Java MCQ Set 2

1. Which of these packages contains the exception StackOverflowError?

A. java.lang

B. java.util

C. java.io

D. java.system

2. Which of these methods can be used to find the length of a string in Java?

A. getSize()

B. length()

C. getLength()

D. size()

3. What is the return type of the main method?

A. void

B. int

C. float

D. char

4. Which keyword is used in the declaration of a subclass?

A. implements

B. extends

C. inherits

D. imports

5. Which of these can be used to create an abstract class?

A. final

B. static

C. abstract

D. private

6. Which of the following is true about inheritance in Java?

A. Multiple inheritance is allowed

B. Java supports single inheritance

C. Java supports hybrid inheritance

D. Java does not support inheritance

7. What is the default value of a static variable?

A. 0

B. null

C. depends on the data type

D. not defined

8. Which operator is used by Java run-time implementations to free the memory of an object?

A. delete

B. free

C. new

D. none

9. Which of the following is not a method of the Object class?

A. finalize()

B. equals()

C. wait()

D. notifyAll()

10. What is byte code in the context of Java?

A. Code written in byte language

B. Code generated after compilation

C. Code generated during execution

D. None of the above

11. Which of the following is a valid keyword in Java?

A. interface

B. string

C. Float

D. unsigned

12. Which of the following is not a valid Java keyword?

A. strictfp

B. constant

C. import

D. native

13. What is the size of int variable?

A. 8 bit

B. 16 bit

C. 32 bit

D. 64 bit

14. What is the return type of the hashCode() method in the Object class?

A. Object

B. int

C. long

D. void

15. Which of these operators can be used to concatenate two or more String objects?

A. +

B. -

C. *

D. &

16. Which of the following is not a valid flow control statement?

A. break

B. continue

C. exit

D. return

17. Which keyword is used for exception handling in Java?

A. catch

B. throw

C. throws

D. finally

18. Which of the following is the correct way of implementing an interface?

A. class Demo implements Runnable {}

B. class Demo extends Runnable {}

C. class Demo imports Runnable {}

D. none of the mentioned

19. Which of the following is used to find and fix bugs in the Java programs?

A. JVM

B. JRE

C. JDK

D. JDB

20. Which of the following is a reserved keyword in Java?

A. extern

B. implement

C. synchronized

D. run