ObjectStreamTest.java Source code

Introduction

Here is the source code for ObjectStreamTest.java

Source

/*
   This program is a part of the companion code for Core Java 8th ed.
   (http://horstmann.com/corejava)
    
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
    
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
    
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Date;
import java.util.GregorianCalendar;

/**
 * @version 1.10 17 Aug 1998
 * @author Cay Horstmann
 */
public class ObjectStreamTest {
    public static void main(String[] args) {
        Employee harry = new Employee("Harry Hacker", 50000, 1989, 10, 1);
        Manager carl = new Manager("Carl Cracker", 80000, 1987, 12, 15);
        carl.setSecretary(harry);
        Manager tony = new Manager("Tony Tester", 40000, 1990, 3, 15);
        tony.setSecretary(harry);

        Employee[] staff = new Employee[3];

        staff[0] = carl;
        staff[1] = harry;
        staff[2] = tony;

        try {
            // save all employee records to the file employee.dat
            ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("employee.dat"));
            out.writeObject(staff);
            out.close();

            // retrieve all records into a new array
            ObjectInputStream in = new ObjectInputStream(new FileInputStream("employee.dat"));
            Employee[] newStaff = (Employee[]) in.readObject();
            in.close();

            // raise secretary's salary
            newStaff[1].raiseSalary(10);

            // print the newly read employee records
            for (Employee e : newStaff)
                System.out.println(e);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

class Employee implements Serializable {
    public Employee() {
    }

    public Employee(String n, double s, int year, int month, int day) {
        name = n;
        salary = s;
        GregorianCalendar calendar = new GregorianCalendar(year, month - 1, day);
        hireDay = calendar.getTime();
    }

    public String getName() {
        return name;
    }

    public double getSalary() {
        return salary;
    }

    public Date getHireDay() {
        return hireDay;
    }

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

    public String toString() {
        return getClass().getName() + "[name=" + name + ",salary=" + salary + ",hireDay=" + hireDay + "]";
    }

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

class Manager extends Employee {
    /**
     * Constructs a Manager without a secretary
     * @param n the employee's name
     * @param s the salary
     * @param year the hire year
     * @param month the hire month
     * @param day the hire day
     */
    public Manager(String n, double s, int year, int month, int day) {
        super(n, s, year, month, day);
        secretary = null;
    }

    /**
     * Assigns a secretary to the manager.
     * @param s the secretary
     */
    public void setSecretary(Employee s) {
        secretary = s;
    }

    public String toString() {
        return super.toString() + "[secretary=" + secretary + "]";
    }

    private Employee secretary;
}