Free Test Interfaces and Abstrac... – JAVA

Q1: What is an interface in Java?

A. A class with abstract methods B. A blueprint of a class with abstract methods only C. A subclass D. A final class

Q2: Can interfaces have default methods in Java?

A. No B. Yes, since Java 8 C. Only abstract methods allowed D. Only in abstract classes

Q3: Which keyword is used to implement an interface?

A. extends B. implements C. inherits D. uses

Q4: What is true about abstract classes?

A. They cannot have constructors B. They can’t have implemented methods C. They can have both abstract and concrete methods D. They must be static

Q5: Can a class implement multiple interfaces?

A. No B. Yes C. Only one allowed D. Only abstract class allowed

Q6: Which of the following cannot be instantiated?

A. Interface B. Abstract class C. Concrete class D. Both A and B

Q7: What does an interface not allow until Java 7?

A. Variables B. Abstract methods C. Static blocks D. Inheritance

Q8: Can an abstract class extend another abstract class?

A. Yes B. No C. Only if final D. Only if static

Q9: Which interface method modifier is implicitly added in Java?

A. public B. private C. protected D. static

Q10: Can a class be both abstract and final?

A. Yes B. No C. Only if interface D. Only with static methods

Q11: What is an interface in Java? (11)

A. A class with abstract methods B. A blueprint of a class with abstract methods only C. A subclass D. A final class

Q12: Can interfaces have default methods in Java? (12)

A. No B. Yes, since Java 8 C. Only abstract methods allowed D. Only in abstract classes

Q13: Which keyword is used to implement an interface? (13)

A. extends B. implements C. inherits D. uses

Q14: What is true about abstract classes? (14)

A. They cannot have constructors B. They can’t have implemented methods C. They can have both abstract and concrete methods D. They must be static

Q15: Can a class implement multiple interfaces? (15)

A. No B. Yes C. Only one allowed D. Only abstract class allowed

Q16: Which of the following cannot be instantiated? (16)

A. Interface B. Abstract class C. Concrete class D. Both A and B

Q17: What does an interface not allow until Java 7? (17)

A. Variables B. Abstract methods C. Static blocks D. Inheritance

Q18: Can an abstract class extend another abstract class? (18)

A. Yes B. No C. Only if final D. Only if static

Q19: Which interface method modifier is implicitly added in Java? (19)

A. public B. private C. protected D. static

Q20: Can a class be both abstract and final? (20)

A. Yes B. No C. Only if interface D. Only with static methods

Q21: What is an interface in Java? (21)

A. A class with abstract methods B. A blueprint of a class with abstract methods only C. A subclass D. A final class

Q22: Can interfaces have default methods in Java? (22)

A. No B. Yes, since Java 8 C. Only abstract methods allowed D. Only in abstract classes

Q23: Which keyword is used to implement an interface? (23)

A. extends B. implements C. inherits D. uses

Q24: What is true about abstract classes? (24)

A. They cannot have constructors B. They can’t have implemented methods C. They can have both abstract and concrete methods D. They must be static

Q25: Can a class implement multiple interfaces? (25)

A. No B. Yes C. Only one allowed D. Only abstract class allowed

Quiz for Interfaces and Abstract Classes

Q1: What is an interface in Java?

Q2: Can interfaces have default methods in Java?

Q3: Which keyword is used to implement an interface?

Q4: What is true about abstract classes?

Q5: Can a class implement multiple interfaces?

Q6: Which of the following cannot be instantiated?

Q7: What does an interface not allow until Java 7?

Q8: Can an abstract class extend another abstract class?

Q9: Which interface method modifier is implicitly added in Java?

Q10: Can a class be both abstract and final?

Q11: What is an interface in Java? (11)

Q12: Can interfaces have default methods in Java? (12)

Q13: Which keyword is used to implement an interface? (13)

Q14: What is true about abstract classes? (14)

Q15: Can a class implement multiple interfaces? (15)

Q16: Which of the following cannot be instantiated? (16)

Q17: What does an interface not allow until Java 7? (17)

Q18: Can an abstract class extend another abstract class? (18)

Q19: Which interface method modifier is implicitly added in Java? (19)

Q20: Can a class be both abstract and final? (20)

Q21: What is an interface in Java? (21)

Q22: Can interfaces have default methods in Java? (22)

Q23: Which keyword is used to implement an interface? (23)

Q24: What is true about abstract classes? (24)

Q25: Can a class implement multiple interfaces? (25)