Practice Why Use Interfaces? (2.3) - Chapter 12: Inheritance, Interface, and Polymorphism

Practice: Why use Interfaces?

Lesson 2.3Inheritance, Interface, and Polymorphism

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10 questions

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4 cards from this section. Quick, good the night before a test.
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4 questions · about 3 min · pass mark 70%. Hints available.
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6 sample questions

Question 1.
What is an interface in Java?
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Think of it as a contract.
Question 2.
Can a class implement multiple interfaces?
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Recall the definition of multiple inheritance.
3Question 3.
What is an interface in Java?
- A class
- A collection of abstract methods
- A concrete implementation
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Consider what ‘abstract’ means.
4Question 4.
Is it possible for a class to implement more than one interface?
- True
- False
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Think about how different functionalities might be integrated.
Question 5.
Imagine you're creating a software application for an online store. Define an interface called 'Purchasable' with a method 'purchase()'. Implement this interface in classes 'Book', 'Electronics', and 'Clothing'. Describe how each class might behave differently when 'purchase()' is called.
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Think about the different purchasing processes for various item types.
Question 6.
You are asked to improve the maintainability of an application by introducing interfaces. Current classes have tightly-bound dependencies. Explain how you would use interfaces to achieve this goal.
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Consider how you can decouple components in your system.

6 more questions in this section. Enroll free to practise them all.