persontest.java

《JAVA程序设计教程》源代码

//PersonTest.java
import java.text.*;

public class PersonTest
{  
   public static void main(String[] args)
   {  
      Person[] people = new Person[2];
      people[0]= new Employee("张三", 50000);// 给员工与学生对象数组赋值
      people[1]= new Student("李四", "计算机科学");
      for (int i = 0; i < people.length; i++)// 打印输出关于人类的基本信息
      {  
         Person p = people[i];
         System.out.println(p.getName() + ", " + p.getDescription());
      }
   }
}

abstract class Person//抽象人类                       
{  
   public Person(String n)
   {  
      name = n;
   }

   public abstract String getDescription();//抽象方法    

   public String getName()
   {  
      return name;
   }

   private String name;
}

class Employee extends Person//子类1：员工                  
{  
   public Employee(String n, double s)
   {  
                                          
      super(n);// 传递信息到父类构造函数
      salary = s;
   }

   public double getSalary()
   {  
      return salary;
   }

   public String getDescription()//子类1的方法：员工工资               
   {  
      NumberFormat formatter
         = NumberFormat.getCurrencyInstance();
      return "员工的工资是："+ formatter.format(salary);
   }

   public void raiseSalary(double byPercent)
   {  
      double raise = salary * byPercent/100;
      salary += raise;
   }
   private double salary;
}

class Student extends Person//子类2 ：学生               
{  
     public Student(String n, String m)
   {  
      super(n);// 传递字符n到父类构造函数
      major = m;
   }

   public String getDescription()//子类2 的方法 ，得到学生的专业        

   {  
      return "学生的专业是：" + major;
   }

   private String major;
}