15.8.2. Comparator Interface

Try these first

1. 1.

   What is the purpose of the Comparator interface in Java?

   Hint

   Think about when you'd need to sort items differently.

2. 2.

   What method do you need to implement in a Comparator?

   Hint

   What are the two objects you compare?

3. 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

   Hint

   Think about what flexibility you need beyond natural ordering.

4. 4.

   True or False: A Comparator can only sort objects in increasing order.

   • True
   • False

   Hint

   Consider how you could reverse the sorting order.

5. 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.

   Hint

   Think about the significance of each attribute when comparing.

6. 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.

   Hint

   What condition checks will you need?