/**
@version 1.00 2008-5-25 @author WANGYIFEI
*/
import java.text.*;public class PersonTest{ public static void main(String[] args)
{ 
Person[] people = new Person[2]; // fill the people array with Student and Employee objects people[0] = new Employee("Harry Hacker", 50000); people[1] = new Student("Maria Morris", "computer science"); // print out names and descriptions of all Person objects for (int i = 0; i < people.length; i++) { Person p = people[i]; System.out.println(p.getName() + ", " + p.getDescription());
} }}abstract class Person{ public Person(String n) { name = n; } public abstract String getDescription(); public String getName() { return name; } private String name;}class Employee extends Person{ public Employee(String n, double s) { // pass name to superclass constructor super(n); salary = s; } public double getSalary() { return salary; } public String getDescription() { NumberFormat formatter = NumberFormat.getCurrencyInstance(); return "an employee with a salary of " + formatter.format(salary); } public void raiseSalary(double byPercent) { double raise = salary * byPercent / 100; salary += raise; } private double salary;}class Student extends Person{ /** @param n the student's name @param m the student's major */ public Student(String n, String m) { // pass n to superclass constructor super(n); major = m; } public String getDescription() { return "a student majoring in " + major; } private String major;}