Chapter 11: Problem 20

If a subclass extends a superclass with an abstract method, what must you do in the subclass?

Short Answer

Expert verified

Answer: When a subclass extends a superclass with an abstract method, it must provide an implementation for the inherited abstract method. To do this, the subclass needs to override the abstract method with a matching method signature (name, return type, and parameters), use the '@Override' annotation before the method, ensure the access level is not more restrictive, and write the method body to fulfill the superclass's abstract method description.

Step by step solution

Understanding abstract methods and inheritance

Abstract methods are methods declared in an abstract class without an implementation. When a subclass extends a superclass with an abstract method, it inherits the abstract method as well. The subclass is expected to provide the implementation for this inherited abstract method.

Implement the abstract method in the subclass

To ensure the functionality and correct behavior of the subclass, you must provide the implementation of the abstract method in your subclass. The subclass must override the abstract method with its own method definition, which includes the method's body.

Use the '@Override' annotation

It is a good practice to use the '@Override' annotation above the implemented abstract method in your subclass. This tells the compiler that the method is intended to override a method in the superclass and helps to catch errors at compile-time, such as misspelling the method name or parameter types.

Match the method signature

When implementing the abstract method in the subclass, make sure that the method signature (i.e., the method name, return type, and parameters) matches the abstract method's signature in the superclass. The access level of the implemented method in the subclass cannot be more restrictive than that of the abstract method in the superclass.

Implement the method body

Write the body of the method to provide the specific functionality for the subclass. The implementation should match the purpose and description of the abstract method as defined in the superclass. Implementing the method body completes the process of fulfilling the requirement of a subclass to provide the implementation of inherited abstract methods.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Computer Science Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

If a subclass extends a superclass with an abstract method, what must you do in the subclass?

Short Answer

Step by step solution

Understanding abstract methods and inheritance

Implement the abstract method in the subclass

Use the '@Override' annotation

Match the method signature

Implement the method body

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Computer Science Textbooks

Computer Programming

Data Structures

Data Representation in Computer Science

Problem Solving Techniques

Algorithms in Computer Science

Computer Systems

Study anywhere. Anytime. Across all devices.