Exercises: Inheritance
Work on these exercises within IntelliJ using the java-web-dev-projects
project you already created. Add a new package called technology
to your exercises
directory.
- Class design: Create a new class called
Computer
. Before you add any more code, know that you will need to add two additional classes:Laptop
andSmartPhone
.
Before you start coding anything inside these classes, diagram how the three classes are going to be related to each other. Remember to add properties and methods to your diagram!
For a parent class add
3 properties
,2 methods
, and aconstructor
.For a child class add at least
1 additional property
and1 additional method
.Class implementation: Implement your design and test it in a
Program.java
class.
- Try to add three
JUnit tests
per class!
- Abstract class design: Consider the group of classes that you designed. Suppose you had a web program that used these classes, and you needed to assign a unique ID to every object created from one of these classes within the application. Therefore, each such class should have an
Id
property, and no two objects created from any of the classes may have the same value forId
. Create an abstract class,AbstractEntity
, that contains the behavior for assigning and accessing such a unique ID for each class that extends it. Add this class to your program above, and addAbstractEntity
to the class hierarchy in the correct place.