15.8. Comparators and Comparable

Try these first

1. 1.

   What method does the Comparable interface require to be implemented?

   Hint

   Think about how one object might compare itself to another.

2. 2.

   What is the purpose of the Comparator interface?

   Hint

   Consider scenarios where you might want different sorting criteria.

3. 3.

   What does the Comparable interface provide?

   • Custom ordering
   • Natural ordering
   • Does nothing

   Hint

   Focus on the primary role of the Comparable interface.

4. 4.

   True or False: The Comparator interface can only be used for natural ordering.

   • True
   • False

   Hint

   Consider the different functionalities of Comparable and Comparator.

5. 5.

   Write a Java class that implements Comparable and gives a natural ordering based on two attributes - age and name.

   Hint

   Think about the logic needed to handle the two comparisons together.

6. 6.

   Implement a Comparator for a class that represents a book with attributes for title and publish year. Sort it first by year, then by title if years are the same.

   Hint

   You’ll need to use two comparisons in your Comparator to account for both criteria.