Inheritance and Interfaces - Building Java Programs: A Back to Basics Approach - page 557

15 public String getVacationForm() {
16 return "yellow";
17 }
18 }

Now let's think about implementing the Secretary subcategory. As we mentioned
in the previous section, every Secretary is also an Employee and, consequently,
retains the abilities that Employee s have. Secretaries also have one additional ability:
the ability to take dictation. If we wrote Secretary as a standalone class, its code
would not reflect this relationship very elegantly. We would be forced to repeat all of
the same methods from Employee with identical behavior. Here is the redundant class:

1 // A redundant class to represent secretaries.
2 public class Secretary {
3 public int getHours() {

4 return 40;

5 }
6
7 public double getSalary() {
8 return 40000.0;

9 }
10
11 public int getVacationDays() {
12 return 10;

13 }
14
15 public String getVacationForm() {

16 return "yellow";

17 }
18
19 // this is the only added behavior
20 public void takeDictation(String text) {

21 System.out.println("Dictating text: " + text);

22 }
23 }

The only code unique to the Secretary class is its takeDictation method.
What we'd really like to do is to be able to copy the behavior from class Employee
without rewriting it in the Secretary class file.