从子类的超类调用方法返回值0

Question

Pretty new to Java, this is for an assignment. Basically what I'm trying to do is the user inputs the amount of hours they've worked, their hourly rate, and their straight time hours and the program outputs their net pay.

I can calculate the gross pay just fine but the assignment requires me to calculate net pay within a subclass by calling the calc_payroll and tax methods from the superclass but it keeps returning a value of zero. I thought maybe there was something wrong with my tax method so I tried returning the gross pay from the subclass but it still returned zero.

I'm really stumped here, can anyone help?

Superclass:

class Pay
{

   private float hoursWorked;
   private float rate;
   private int straightTimeHours;

   public double calc_payroll()
   {
      double straightTimePay = rate * straightTimeHours;
      double excessPay = (rate * 1.33) * (hoursWorked - straightTimeHours);
      double grossPay = straightTimePay + excessPay;

      return grossPay;
   }

   public double tax(double a)
   {
      double taxRate;
      double netPay;

      if(a <= 399.99)
         taxRate = 0.08;
      else if(a > 399.99 && a <= 899.99)
         taxRate = 0.12;
      else
         taxRate = 0.16;

      netPay = a - (a * taxRate);

      return netPay;
   }

   public void setHours(float a)
   {
      hoursWorked = a;
   }

   public float getHours()
   {
      return hoursWorked;
   }

   public void setRate(float a)
   {
      rate = a;
   }

   public float getRate()
   {
      return rate;
   }

   public void setHrsStr(int a)
   {
      straightTimeHours = a;
   }

   public int getHrsStr()
   {
      return straightTimeHours;
   }

}

Subclass:

class Payroll extends Pay
{

   public double calc_payroll()
   {
      Pay getVariables = new Pay();

      double getGrossPay = getVariables.calc_payroll();
      double finalNetPay = getVariables.tax(getGrossPay);

      return finalNetPay; //This returns a value of zero
      //return getGrossPay; This also returns a value of zero
   }

}

Main Method:

import java.util.*;

class Assign2A
{

   public static void main(String args[])
    {
      float userHours;
      float userRate;
      int userStraight;
      Scanner userInput = new Scanner(System.in);

      System.out.println("I will help you calculate your gross and net pay!");
      System.out.println("Please enter the number of hours you have worked: ");
      userHours = Float.valueOf(userInput.nextLine());
      System.out.println("Please enter your hourly pay rate: ");
      userRate = Float.valueOf(userInput.nextLine());
      System.out.println("Please enter the number of straight hours required: ");
      userStraight = Integer.parseInt(userInput.nextLine());

      Pay object = new Pay();
      object.setHours(userHours);
      object.setRate(userRate);
      object.setHrsStr(userStraight);

      Payroll objectTwo = new Payroll();

      System.out.println("========================================");
      System.out.println("Your gross pay is: ");
      System.out.println("$" + object.calc_payroll());
      System.out.println("Your net pay is: ");
      System.out.println("$" + objectTwo.calc_payroll());
      System.out.println("Thank you, come again!");
   }

}

Typical Output:

 ----jGRASP exec: java Assign2A

I will help you calculate your gross and net pay!
Please enter the number of hours you have worked: 
500
Please enter your hourly pay rate: 
25
Please enter the number of straight hours required: 
100
========================================
Your gross pay is: 
$15800.0
Your net pay is: 
$0.0
Thank you, come again!

 ----jGRASP: operation complete.

Answer 1

Several issues. For one, you're creating a Payroll object:

  Payroll objectTwo = new Payroll();

  //.....
  System.out.println("$" + objectTwo.calc_payroll());

Not giving it any value, and then are surprised when it holds a value of 0.

You should use one single object here, a Payroll object, not a Pay object, fill it with valid data, and call both methods on this single object.

Secondly, your Payroll class is completely wrong. You have:

class Payroll extends Pay {

    public double calc_payroll() {
        Pay getVariables = new Pay();

        double getGrossPay = getVariables.calc_payroll();
        double finalNetPay = getVariables.tax(getGrossPay);

        return finalNetPay; // This returns a value of zero
        // return getGrossPay; This also returns a value of zero
    }

}

But it should not create a Pay object but rather use the super methods as needed. To better help you with this, you will have to tell us your complete assignment requirements because you're making wrong assumptions about the assignment, I believe.