Week 4 - interfaces

Question 1

Why use interfaces?

Answer 1

Java doesn’t support multiple inheritance so you can’t extend from 2 classes but you can extend from a single class and implement interfaces.

You can implement multiple interfaces

Question 2

What does the Comparable interface do?

Answer 2

Allows you to compare objects it sort them in order

Any class which implements the comparable interface must code a method called compareTo()

Objects that implement this interface can be sorted using Arrays.sort()

Question 3

An interface describes…

Answer 3

A set of method signatures that must be implemented.

Question 4

A class that implements an interface must implement all the public methods declared in the interface. T or F?

Answer 4

True