Question

I’m trying to make program that has a Person class with one field : name(String) and accessor and mutator. and then make a second class Student ( extends Person class) – one field: id and accessor and mutator of id. then to test it make an object and assign name and id and print out result.

This is what I have so far:

Person Class:

/*
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 * and open the template in the editor.
 */
package person;

/**
 *
 * @author Administrator
 */
public class Person {

    /**
     * @param args the command line arguments
     */

    private String name;

    public void setName(String n)
    {
        name = n;
    }

    public String getName(String n)
    {
        return name;
    }
}

Student class //I think this is the class with the extension:

/*
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 * and open the template in the editor.
 */
package person;


public class Student extends Person {

    public int idNumber;

    Student(String name, int idNumber) {

    }

    public void setID(int id)
    {
        idNumber = id;
    }

    public int getID(int id)
    {
        return idNumber;
    }

}

and then the main class to test the result:

/*
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 * and open the template in the editor.
 */
package person;

import java.util.Scanner;

/**
 *
 * @author Administrator
 */
public class MainStudentID {


    public static void main(String[] args)
    {
        Scanner keyboard = new Scanner(System.in);

        System.out.println("Enter Students name: ");
        String name = keyboard.nextLine();

        System.out.println("Enter Students ID Number:");
        int idNumber = keyboard.nextInt();


        Student Student = new Student(name, idNumber);

        System.out.println("Your name is: " + Student.person.getName());
        System.out.println("Your id Number is: " + Student.Student.getID());




    }

}

I’m not sure what I am doing wrong, and I apologize for my crappy code, first time learning about the topic of class extensions.

Answer 1

You need to set the values of name and id in your Student constructor. You’re not storing them which is why you’re not getting a result when you try to print.

You also need to get rid of the parameters in your get methods.

Person Class:

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package person;

/**
 *
 * @author Administrator
 */
public class Person {

    /**
     * @param args the command line arguments
     */

    private String name;

    public Person(String n)
    {
        name = n;
    }

    public void setName(String n)
    {
        name = n;
    }

    public String getName()
    {
        return name;
    }
}

Student class

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package person;


public class Student extends Person {

    public int idNumber;

    Student(String name, int idNumber) {
        super(name);
        this.idNumber = idNumber;
    }

    public void setID(int id)
    {
        idNumber = id;
    }

    public int getID()
    {
        return idNumber;
    }

}