Computer Science 225
Advanced Programming

Spring 2017, Siena College

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Overriding BlueJ Project

Click here to download a BlueJ project for Overriding.

Overriding Source Code

The Java source code for Overriding is below. Click on a file name to download it.

Overriding.java

/*
 * Example Overriding: overriding methods in subclasses
 *
 * Jim Teresco, Siena College, Computer Science 225, Spring 2017
 *
 * Based heavily on example from Darren Lim
 */

import java.util.ArrayList;

class Student
{
    public String name = "Fred";
    
    protected void getName()
    {
        System.out.println(name);
    }       
}


class Undergraduate extends Student
{
    @Override
    protected void getName()
    {
        System.out.println("Undergraduate : " + name);
    }
} 

class Freshman extends Undergraduate
{
}

class Graduate extends Student
{
    @Override
    protected void getName()
    {
        System.out.println("Graduate : " + name);
    }

}

class Phd extends Graduate
{
    @Override
    protected void getName()
    {
        System.out.println("Phd : " + name);
    }
}

public class Overriding 
{

    public static void main(String[] args) 
    {
        // populate an ArrayList with Student objects and instances of derived classes
        ArrayList<Student> students = new ArrayList<>();
        students.add(new Student());
        students.add(new Undergraduate());
        students.add(new Freshman());
        students.add(new Graduate());
        students.add(new Phd());
        
        // let's call each one's getName method
        for (Student s : students) {
            
            s.getName();
        }
    
    }
}