4.7. Exercises: Classes and Objects

Work on these exercises in the IntelliJ java-web-dev-exercises project.

1. Open up the file, Student.java, and add all of the necessary getters and setters. Think about the access level each field and method should have, and try reducing the access level of at least one setter to less than public.

   Check your solution

2. Instantiate the Student class using yourself as the student. For the numberOfCredits give yourself 1 for this class and a GPA of 4.0 because you are a Java superstar!

3. In the school package, create a class Course with at least three fields. Before diving into IntelliJ, try using pen and paper to work through what these might be. At least one of your fields should be an ArrayList or HashMap, and you should use your Student class.

   Check your solution

4. In the school package, create a class Teacher with four fields: firstName, lastName, subject, and yearsTeaching. Add getters and setters to the class and add the access level to each field and method in the class. When adding your getters and setters, think about what we read about in the section on Encapsulation.

   1. What access modifier restricts access the most for what we need?

   2. If it is a field, could we restrict the access to private and use getters and setters?

   3. If we do set fields to private, what access level do we have to give our getters and setters?