Java Enums MCQ

Enums, short for enumerations, are a unique kind of class in Java. They allow for a variable to be a set of predefined constants. This characteristic ensures more type safety, cleaner code, and other advantages. How familiar are you with Java enums? Let’s find out with this beginner's quiz!

Each question is followed by the correct answer and an explanation to help reinforce your knowledge.

1. Which of the following best describes an enum in Java?

a) A special kind of interface
b) A type of method
c) A way to declare arrays
d) A special class that represents a group of constants

2. How do you define an enum that represents days of the week?

a) enum DAYS {MON, TUE, WED, THU, FRI, SAT, SUN}
b) enum DAYS [MON, TUE, WED, THU, FRI, SAT, SUN]
c) Days enum = {MON, TUE, WED, THU, FRI, SAT, SUN}
d) enum DAYS

3. Which method can be used to get the ordinal value of an enum constant?

a) getValue()
b) getOrdinal()
c) getOrder()
d) ordinal()

4. Can an enum have a constructor?

a) Yes, and it can be public
b) Yes, but it must always be private
c) No, enums cannot have constructors
d) Yes, but it must be protected

5. Can you override the toString() method in an enum?

a) Yes
b) No
c) Only in abstract enums
d) Only if the enum has attributes

6. Which method can be used to get an enum constant by its string name?

a) Enum.valueOf()
b) Enum.getByName()
c) Enum.get()
d) Enum.fromString()

7. Can enums extend other classes in Java?

a) Yes
b) No
c) Only abstract classes
d) Only other enums

8. What happens when you try to print an enum constant directly?

a) It throws an error
b) It prints the ordinal value
c) It prints the name of the constant
d) It prints the fully qualified class name of the enum constant

9. Can an enum be declared inside a class?

a) Yes, and it is always static
b) No
c) Only if the class is abstract
d) Only in the main class

10. Which of the following statements about enums is NOT correct?

a) Enums can implement interfaces
b) Enums can have attributes and methods
c) Enums can be instantiated using the new keyword
d) Enums can have constructors

Enums provide a concise and type-safe way to represent a fixed set of related constants in Java. They are versatile and can be employed in a variety of use cases, from simple value collections to sophisticated type patterns. If you found this quiz informative, continue delving deeper into Java's features and enhance your understanding. Happy coding!



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