Practice Comparator Interface (15.8.2) - Collections and Generics - Advanced Programming

Practice: Comparator Interface

Lesson 15.8.2Collections and Generics

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10 questions

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6 sample questions

Question 1.
What is the purpose of the Comparator interface in Java?
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Think about when you'd need to sort items differently.
Question 2.
What method do you need to implement in a Comparator?
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What are the two objects you compare?
3Question 3.
What does the Comparator interface allow you to do?
- A. Sort objects naturally
- B. Define custom ordering for objects
- C. Force comparison between two objects
- D. Merge multiple lists
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Think about what flexibility you need beyond natural ordering.
4Question 4.
True or False: A Comparator can only sort objects in increasing order.
- True
- False
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Consider how you could reverse the sorting order.
Question 5.
Create a Comparator for a class that represents products in a store. The Comparator should first compare products by price, and then by name if prices are the same.
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Think about the significance of each attribute when comparing.
Question 6.
Imagine you have a data structure that needs to sort student records by GPA, and if two students have the same GPA, by last names. Design your solution using the Comparator interface.
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What condition checks will you need?

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