Top Java MCQs with Answers for Job Interviews

Java is the most popular and versatile programming language used in back-end engineering. The language functions on multiple devices, including gaming, consoles, mobile devices, notebooks, computers, medical devices, and much more.

Drawing its syntax and rules from the foundations of C++ and C languages, Java offers a familiar yet powerful environment for developers to craft scalable and reliable applications across diverse platforms.

It is also crucial to acknowledge that Java is entirely different from JavaScript. JavaScript is not compiled. However, Java needs to be compiled. Furthermore, Java can function anywhere; however, JavaScript only functions on web browsers.

Java Multiple Choice Questions with Answers

This list of MCQ Java interview questions, followed by answers, will provide you with numerous questions on different Java concepts.

Topics are crafted by subject experts for professionals, developers, and engineers to learn and practice to clear their upcoming developer interviews.

Some of the most commonly asked questions at Java interviews are:

Q1. Java programming was invented by:

1. Dennis Ritchie
2. Guido Van Rossum
3. James Gosling
4. Bjarne Stroustrup

Answer: C. James Gosling

Q2. Which of the following statements is correct regarding Java?

1. Java is a platform-independent programming language
2. Java is a code-dependent programming language
3. Java is a sequence-dependent programming language
4. Java is a platform-independent programming language

Answer: D. Java is a platform-independent programming language.

Q3. To compile, execute, and debug the Java programs, which component is implemented?

1. JRE
2. JDK
3. JVM
4. JIT

Answer: B. JDK

Q4. Which of the following is not a feature of Java?

1. Extensible and dynamic
2. Portable
3. Object-oriented
4. Use of pointers

Answer: D. Use of Pointers

Q5. Which of the following is not used for variable names in Java?

1. Keyword
2. Identifier
3. Keyword and identifier
4. None of the above

Answer: A. Keyword

Q6. Which one is the extension of Java code files?

1. .js
2. .java
3. .class
4. .txt

Answer: B. .java

Q7. To set the Java part, which of the following environment variables is used?

1. JavaPATH
2. JAVA
3. JAVA_HOME
4. Maven_Path

Answer: C. JAVA_HOME

Q8. Which one is not the Java OOPS concept?

1. Compilation
2. Inheritance
3. Encapsulation
4. Polymorphism

Answer: A. Compilation

Q9. Which of the following types of polymorphism is used in the Java programming language?

1. Execution time polymorphism
2. Multilevel polymorphism
3. Multiple polymorphism
4. Compile time polymorphism

Answer: D. Compile time polymorphism

Q10. Which of the following is a compiled Java class extension?

1. .java
2. .js
3. .class
4. .txt

Answer: C. .class

Q11. When Java runs out of memory, which exception is thrown?

1. MemoryFullException
2. MemoryError
3. OutOfMemoryError
4. MemoryOutOfBoundsException

Answer: C. OutOfMemoryError

Q12. Which, among the following, is a Java selection statement?

1. Continue
2. Break
3. for()
4. if()

Answer: D. if()

Q13. For finding interfaces in Java, which of the following keywords is used?

1. Interface
2. interface
3. Intf
4. intf

Answer: B. interface

Q14. Which of the following options isn’t a Java Profiler?

1. JConsole
2. JVM
3. JProfiler
4. Eclipse Profiler

Answer: B. JVM

Q15. Which package includes the exception stack overflow in Java?

1. java.util
2. java.io
3. java.lang
4. java.system

Answer: C. java.lang

Q16. How many types of primitive data in Java are present?

1. 6
2. 7
3. 9
4. 8

Answer: D. 8

Q17. Choose the correct size of float and double in Java.

1. 32 and 64
2. 64 and 32
3. 32 and 32
4. 64 and 64

Answer: A. 32 and 64

Q18. In which of the following cases is automatic type conversion possible?

1. Short to int
2. Byte to int
3. Int to long
4. Long to int

Answer: C. Int to long

Q19. What will be the output of the code given below?

1. 24 I
2. I
3. Throws exception
4. Compile error

Answer: A. 24 I

Q20. What will be the output of the program given below?

1. -127
2. 129
3. 127
4. 2

Answer: A. -127

Q21. What is received by the method when an array is passed to it?

1. Length of the array
2. A copy of the array
3. Copy of first element
4. The reference of the array

Answer: D. The reference of the array

Q22. What are arrays in Java?

1. Objects
2. Primitive data type
3. Object references
4. None

Answer: A. Objects

Q23. When does object creation take place with a new keyword?

1. Depends on the code
2. At run time
3. At compile time
4. None

Answer: B. At run time

Q24. What is the correct definition of a package?

1. Collection of classes
2. Collection of editing tools
3. Collection of interfaces
4. Collection of interfaces and classes

Answer: D. Collection of interfaces and classes

Q25. Which keyboard amongst the following options, makes a variable belong to a clause instead of being defined for a specific instance of the class?

1. Static
2. Volatile
3. Final
4. Abstract

Answer: A. static

Q26. What is the output of the program given below?

1. 0
2. 1
3. -1
4. True

Answer: C. -1

Q27. The class string belongs to which of the following?

1. java.lang
2. java.string
3. java.awt
4. java.applet

Answer: A. java.lang

Q28. What is the return type of a method that doesn’t return any value?

1. Double
2. Void
3. int
4. None

Answer: B. void

Q29. When a method is involved, where does the system store local variables and parameters?

1. Stack
2. Tree
3. Heap
4. Array

Answer: A. Stack

Q30. Which of the following options is Runnable?

1. Interface
2. Class
3. Method
4. Abstract class

Answer: A. Interface

Q31. Which interface is used to declare core methods in Java?

1. Set
2. Collection
3. Comparator
4. EventListener

Answer: B. Collection

Q32. Which among the following is an incorrect Java feature?

1. Dynamic
2. Use of pointers
3. Object oriented
4. Architectural neural

Answer: B. Use of pointers

Q33. Which of the following finds and fixes bugs in the program?

1. JDB
2. JVM
3. JDK
4. JRE

Answer: A. JDB

Q34. In the execution of the divided by zero statement, which of the following exceptions is thrown?

1. ArithmeticException
2. NumberFormatException
3. NullPointerException
4. None

Answer: A. ArithmeticException

Q35. Under which situation, is the finalize() method called?

1. Before a variable goes out of scope
2. Before garbage collection
3. Before an object goes out of scope
4. None

Answer: B. Before garbage collection

Our collection of MCQs serves as a valuable tool in your learning journey. You can do a self-assessment before applying to companies for interviews.

By consistently engaging in such activities, you not only solidify your grasp of Java’s fundamentals but also hone your problem-solving skills crucial for real-world application development.

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