objectfiletest.java

Java2核心技术卷一 配套源码,看了还不错

/**
 * @version 1.01 25 Oct 1997
 * @author Cay Horstmann
 */

import java.io.*;
import corejava.*;

class ObjectFileTest
{  public static void main(String[] args)
   {  try
      {  Employee[] staff = new Employee[3];

         staff[0] = new Employee("Harry Hacker", 35000,
            new Day(1989,10,1));
         staff[1] = new Manager("Carl Cracker", 75000,
            new Day(1987,12,15));
         staff[2] = new Employee("Tony Tester", 38000,
            new Day(1990,3,15));
      
         ObjectOutputStream out = new ObjectOutputStream(new 
            FileOutputStream("employee.dat"));
         out.writeObject(staff);
         out.close();

         ObjectInputStream in =  new
            ObjectInputStream(new FileInputStream("employee.dat"));
         Employee[] newStaff = (Employee[])in.readObject();

         int i;
         for (i = 0; i < newStaff.length; i++)
            newStaff[i].raiseSalary(100);
         for (i = 0; i < newStaff.length; i++)
            newStaff[i].print();
      }
      catch(Exception e)
      {  System.out.print("Error: " + e);
         System.exit(1);
      }
   }
}

class Employee implements Serializable
{  public Employee(String n, double s, Day d)
   {  name = n;
      salary = s;
      hireDay = d;
   }

   public Employee() {}

   public void print()
   {  System.out.println(name + " " + salary 
         + " " + hireYear());
   }

   public void raiseSalary(double byPercent)
   {  salary *= 1 + byPercent / 100;
   }

   public int hireYear()
   {  return hireDay.getYear();
   }

   private String name;
   private double salary;
   private Day hireDay;
}

class Manager extends Employee
{  public Manager(String n, double s, Day d)
   {  super(n, s, d);
      secretaryName = "";
   }
    
   public Manager() {}

   public void raiseSalary(double byPercent)
   {  // add 1/2% bonus for every year of service
      Day today = new Day();
      double bonus = 0.5 * (today.getYear() - hireYear());
      super.raiseSalary(byPercent + bonus);
   }

   public void setSecretaryName(String n)
   {  secretaryName = n;
   }

   public String getSecretaryName()
   {  return secretaryName;
   }

   private String secretaryName;
}