Variable from superclass is not dispalying

Question

I'm having a problem which I cannot fathom why. I have program I'm making where it takes a few inputs and calculates pay, tax, and final pay. Everything is working except the final pay.

this calculates the final pay

import java.util.*;
public class Payroll extends  Pay
{

public double calc_payroll()
  {
    super.calc_payroll();
    super.tax();

    netPay = grossPay - (grossPay * (tax/100));

    return netPay;

  }
}

this calculates pay and tax

import java.util.*;
public class Pay
{
private float hoursWrkd;
private float rate;
private int hoursStr;

float grossPay;
int tax;
float netPay;


public double calc_payroll()
{
    grossPay = getHoursWrkd()*getRate();
    return grossPay;

}

public double tax()
{
    if (grossPay <= 399.99)
    {
        tax = 7;
    }
    else if (grossPay >= 400.00 && grossPay <= 899.99)
    {
        tax = 11;
    }
    else if (grossPay <= 900.00)
    {
        tax = 15;
    }

    return tax;
}


//Get & Set for hours worked
public float getHoursWrkd()
{
    return hoursWrkd;
}
public void setHoursWrkd(float hoursWrkd)
{
    this.hoursWrkd = hoursWrkd;
}
//Get & Set for Rate
public float getRate()
{
    return rate;
}
public void setRate(float rate) {
    this.rate = rate;
}
//Get & Set for hours straight
public int getHoursStr()
{
    return hoursStr;
}
public void setHoursStr(int hoursStr)
{
    this.hoursStr = hoursStr;
}
}

and this displays all

public class CalPayroll extends Pay
{
public void displayInfo()
{
   super.calc_payroll();
   super.tax();

    Payroll colio = new Payroll();
    colio.calc_payroll();

    NumberFormat dollars = NumberFormat.getCurrencyInstance();

    System.out.println("Gross Pay is : " + dollars.format(grossPay));
    System.out.println("Tax is : " + tax + "%");
    System.out.println("Net Pay is : " + dollars.format(netPay));
}

i have more files but those are the ones that just take the input, and call the other files.

The math is correct, however when i try to call the netPay variable and format it, it dosn't display any ammount. With grosspay it works. However my teacher said were supposed to pass grosspay into tax so it can use it, im not sure if that would fix it.

PLease help.

Answer 1

You try to display the netPay from CalPayroll, but this class never computes this value. When you do

Payroll colio = new Payroll();
colio.calc_payroll();

You’re probably expecting the netPay to be calculated in CalPayrool, but you’re actually calculating a separate value in a separate object, which has no effect on the current object.