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Call Superclass method from overridden Subclass method

I'm sure this has a simple solution, but I'm new to Java and can't work it out.
I have a subclass Payroll that extends a superclass Pay, it contains an overridden method called 'calc_payroll'. From this method, I want to call the superclass method of the same name, and assign the output to a variable in the overriding method. My code is below
public class Payroll extends Pay
{
public double calc_Payroll()
{
double grossPay = super.calc_Payroll();
double taxAmt = tax(grossPay);
double netPay = grossPay - taxAmt;
System.out.println(grossPay);
return netPay;
}
}
Below is the code from the calc_payroll method in the superclass
public double calc_Payroll()
{
double otRate = rate * 1.77;
double otHours = ttlHours - stHours;
if(stHours == 0)
{
grossPay = otHours * rate;
}
else
{
grossPay = ((stHours * rate) + (otHours * otRate));
}
System.out.println(stHours + "//" + otHours + "//" + rate);//for testing
return grossPay;
}
the superclass method functions without issue to calculate and return the gross pay when called from a different subclass, but when calling it from a method with the same name, the print line in the code above (that I have labelled for testing) displays zero's for all variables
Code for full 'Pay' class is below as requested
public class Pay
{
private double ttlHours;
private int stHours;
private double rate;
double grossPay = 0.0;
final double TAXL = 0.07;
final double TAXM = 0.1;
final double TAXH = 0.16;
public void SetHours(double a)
{
ttlHours = a;
}
public void SetHoursStr(int a)
{
stHours = a;
}
public void SetRate(double a)
{
rate = a;
}
public double GetHours()
{
return ttlHours;
}
public int GetStHours()
{
return stHours;
}
public double GetRate()
{
return rate;
}
public double taxRate()
{
double taxRate = 0.0;
if(grossPay <= 399.99)
{
taxRate = TAXL;
}
else if(grossPay <= 899.99)
{
taxRate = TAXM;
}
else
{
taxRate = TAXH;
}
return taxRate;
}
public double tax(double grossPay)
{
double ttlTax = 0.0;
if(grossPay < 400.00)
{
ttlTax += (grossPay * TAXL);
}
else if(grossPay < 900.00)
{
ttlTax += (grossPay * TAXM);
}
else
{
ttlTax += (grossPay * TAXH);
}
return ttlTax;
}
public double calc_Payroll()
{
double otRate = rate * 1.77;
double otHours = ttlHours - stHours;
if(stHours == 0)
{
grossPay = otHours * rate;
}
else
{
grossPay = ((stHours * rate) + (otHours * otRate));
}
System.out.println(stHours + "//" + otHours + "//" + rate);//for testing
return grossPay;
}
}
The subclass Payroll contains no other code
Below is the code that accepts user input to assign values to the initialized variables
public class CalPayroll extends Pay
{
Payroll nPay = new Payroll();
Accept Read = new Accept();
public void AcceptPay()
{
char select = '0';
while(select != 'e' && select != 'E')
{
System.out.println("Payroll Computation \n");
System.out.print("Enter number of hours worked (00.0) <0 for Quick exit>: ");
SetHours(Read.AcceptInputDouble());
System.out.print("Enter first number of hours straight (integer or 0 to disable): ");
SetHoursStr(Read.AcceptInputInt());
System.out.print("Enter hourly rate of worker (00.00): ");
SetRate(Read.AcceptInputDouble());
Screen.ScrollScreen('=', 66, 1);
Screen.ScrollScreen(1);
displayInfo();
System.out.println("e to exit, any other letter + <Enter> to continue");
select = Read.AcceptInputChar();
}
}
public void displayInfo()
{
NumberFormat currency = NumberFormat.getCurrencyInstance();
NumberFormat percent = NumberFormat.getPercentInstance();
System.out.println("Gross pay is :" + currency.format(calc_Payroll()));
System.out.println("Tax is :" + percent.format(taxRate()));
System.out.println("Net pay is :" + currency.format(nPay.calc_Payroll()));
Screen.ScrollScreen(1);
}
}
I'm confused!

Its clear from you code that ttlHours, stHours and rate are not initialised with some reasonable value. So when you just call super.calc_Payroll(), values like 0 or 0.0 are used as i explained in my comment. Its good to first set values of these variables before calling super.calc_Payroll().
SetHours(23.4); //some value
SetHoursStr(5); //some value
SetRate(2.3); //some value
Also you don't have constructor for Pay class, try making it and initialising all uninitialised variable in constructor or use setter/getter methods to set and get values.
Since your both classes extends Pay class, it creates the problem which you are facing. When you call SetHours(Read.AcceptInputDouble()), it set the variable inherited by CalPayroll from Pay, not the variables inherited by Payroll class. What you have to do is to set variables for Payroll instance as well as for current class as both extends Pay. Do the following replace your while loop as,
while(select != 'e' && select != 'E')
{
System.out.println("Payroll Computation \n");
System.out.print("Enter number of hours worked (00.0) <0 for Quick exit>: ");
SetHours(Read.AcceptInputDouble());
nPay.SetHours(GetHours());
System.out.print("Enter first number of hours straight (integer or 0 to disable): ");
SetHoursStr(Read.AcceptInputInt());
nPay.SetHoursStr(GetStHours());
System.out.print("Enter hourly rate of worker (00.00): ");
SetRate(Read.AcceptInputDouble());
nPay.SetRate(GetRate());
Screen.ScrollScreen('=', 66, 1);
Screen.ScrollScreen(1);
displayInfo();
System.out.println("e to exit, any other letter + <Enter> to continue");
select = Read.AcceptInputChar();
}

Please post the complete code.
It seems that for some reason your variables of super class method not getting assigned values properly. And they are initialized with their default values which is making everything 0. I'll be able to help better if you paste the complete class.

How do I get the program statement arguments like heightm passed down to other methods?

import java.util.Scanner ;
public class CollinsHealthCalculator {
double ACTIVITY_FACTOR = 1.375;
public static void main (String[] args) {
newHealthCalcDescription ();
Scanner keyboard = new Scanner (System.in);
System.out.println ("What is your weight in pounds? ");
double weightlb = keyboard.nextDouble ();
System.out.println ("What is your height in inches? ");
double heightin = keyboard.nextDouble ();
System.out.println ("What is your age in years? ");
double ageYears = keyboard.nextDouble ();
double WEIGHT_KILOGRAMS = weightlb / 2.2;
double HEIGHT_METERS = heightin * .0254;
double weightkg = WEIGHT_KILOGRAMS;
double heightm = HEIGHT_METERS;
double computingBMI (BMI, weightkg, heightm);
maleBMR (heightm, weightkg, ageYears);
femaleBMR (heightm, weightkg, ageYears);
showResults (BMI, caloriesm, caloriesf);
public static newHealthCalcDescription () {
System.out.println("This calculator will determine your BMI "
+ "(Body Mass Index). While also it will determine the amount "
+ "of calories needed to maintain weight.");
}
//Computing the BMI
public static void computingBMI (double BMI, double weightkg, double heightm){
BMI = weightkg/(Math.pow(heightm, 2));
}
//Computing BMR for male and female
public static void maleBMR (double heightm, double weightkg, double ageYears) {
double HEIGHT_CENTIMETERS = heightm * 100;
double heightcm = HEIGHT_CENTIMETERS ;
double BMRForMales = 13.397 * weightkg + 4.799 * heightcm - 5.677 * ageYears + 88.362;
double caloriesm = Math.round(BMRForMales * 1.375);
}
public static void femaleBMR (double heightm, double weightkg, double ageYears) {
double HEIGHT_CENTIMETERS = heightm * 100;
double heightcm = HEIGHT_CENTIMETERS ;
double BMRForFemales = 9.247 * weightkg + 3.098 * heightcm - 4.330 * ageYears + 447.593;
double caloriesf = Math.round(BMRForFemales * 1.375);
}
public static void showResults (double BMI, double caloriesm, double caloriesf) {
//Show results
System.out.printf ("%nYour BMI is: %7.1f", BMI);
System.out.println ("A BMI between 18.5 to 24.9 is considered normal.");
System.out.println ();
System.out.println ("To maintain current weight:");
System.out.print ("Men need to eat " + caloriesm);
System.out.println (" calories per day.");
System.out.print ("Females need to eat " + caloriesf);
System.out.println (" calories per day.");
}
}
I'm trying to get the code to pass down statements but I'm new to programming and have no clue on how to go about getting method passed down to another method. I've tried researching everywhere but I've had little luck in finding any help. Please help so I can make my programm functional I'm excited to learn just need help.

You can try giving the variables the global scope(outside the method). You may learn about it here.

When you declare a variable inside a method (i.e. code block), it is local to that block. So you cannot use that variable in any other method. Here the best option for you to do is to declare the variable, i.e. like weightkg etc as class variables.

You can change the return type of the methods from void to double and store the returned result and send the results to other methods.
for eg.
public static double computingBMI (double BMI, double weightkg, double heightm){
return weightkg/(Math.pow(heightm, 2));
}

java returning and calling variables

I am new to java and I am trying to make this bmi calculator but I am having trouble returning and calling variables. I am sure that I am doing something very wrong but have been unable to figure out how to properly do this after searching the internet my guess is I do not know what I should be searching. I will post the code, I am getting 4 errors in my main that are as follows:
required: double,double,double,double
found: no arguments
reason: actual and formal argument lists differ in length
I am assuming that I have improperly set up my variables but could really use a bit of guidance. Thank you in advance.
import java.util.Scanner;
public class cs210 {
public double weight;
public double height;
public double bmi;
public double wcal;
public double mcal;
public double age;
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
method1 ();
method2 ();
method3 ();
method4 ();
method5 ();
}
public static void method1 () {
System.out.println ("This program implements a Health Assistance Calculator ");
System.out.println ("Given a weight, height, and age, it will compute:\n");
System.out.println ("BMI - Body Mass Index");
System.out.println ("Calories needed per day to maintain weight");
}
public double method2 (double weight, double height, double wcal, double bmi) {
Scanner keyboard = new Scanner (System.in);
System.out.println ("Please enter your weight:");
weight = keyboard.nextDouble ();
System.out.println ("Press 1 if weight was entered in Kg \n Press 2 if weight was entered in Lbs");
double wunits = keyboard.nextDouble();
if (wunits == 1) {
System.out.println("Thank you");
} else if (wunits == 2){
weight = weight / 2.2;
System.out.println("Thank you");
}
else {
System.out.println ("Please try again");
return 0;
}
System.out.println("Please enter your height:");
height = keyboard.nextDouble ();
System.out.println ("Press 1 if height was entered in meters \n Press 2 if height was entered in inches");
int hunits = keyboard.nextInt();
if(hunits ==1) {
System.out.println("Thank you");
} else if (hunits == 2){
height = height / 0.0254;
}else {
System.out.println("Please try again");
return 0;
}
System.out.println("Please enter your age in years:");
age = keyboard.nextDouble ();
bmi = weight / Math.pow(height, height);
return ( bmi + age + height + weight);
}
public static double method3(double weight, double age, double height) {
double paf = 1.375;
double mcal;
mcal = (13.397 * weight + 4.799 * height + 5.677 * age + 88.362) * paf;
return mcal;
}
public static double method4(double weight, double age, double height, double paf){
double wcal;
wcal = (93247 * weight + 3.098 * height - 4.330 * age + 447.593) * paf;
return wcal;
}
public double method5(double bmi, double mcal, double wcal){
System.out.println("Your BMI is:" + bmi);
System.out.println("A BMI in the range of 18.5 to 24.9 is considered normal\n");
System.out.println("To maintain your current weight:");
System.out.println("Men need" + mcal + "per day");
System.out.println("Women need" + wcal + "per day");
return 0;
}
}

You define method2 like this:
public double method2 (double weight, double height, double wcal, double bmi) {
// ...
It has four parameters, all double, just like your error message said. Then you call it like this:
method2 ();
Without any parameters at all, again just like the error message said. Since you defined it with four parameters, every time you call it you need to do it with four parameters. The values you use as parameters will be the values that the variables weight, height, wcal and bmi gets inside the function, and if you don't have any parameters the computer will not know what values to use for those variables and therefore throw an error to complain. So you could, as an example, do it like this:
method2(34.9, 23.4, 23.5, 34.1); // Just picked four random numbers here.
But looking at the structure of your program, it looks like you don
t want to pass any values to the function at all (since you let the user enter the values inside the function). Then you could just get rid of the parameters, and declare the variables inside the function:
public double method2 () {
double weight, height, wcal, bmi;
// ...
Now the variables will be available inside method2, but not anywhere else. If you want to use the same values later in the other functions, you could instead of declaring them inside your function declare them in your class, and they will become available anywhere in your class, but not anywhere else.
You will have to fix the same issue with the parameters for method3, method4 and method5 as well.

You need to pass parameters when you call to methods. If you call to method
public double method2 (double weight, double height, double wcal, double bmi)
You need to call it to like this method2 (50, 2, 200, 25.5);
When you call in to your other methods such as method3, method4, method5 ; you have to give appropriate parameters to those. But when it comes to your method1. It will not expecting any parameters so you don't want to pass any parameter to that method.
I think this small document will help you to understand method and arguments.
https://docs.oracle.com/javase/tutorial/java/javaOO/arguments.html
Its better to add your BMI logic and method to separate class then within the main method create and object and to the rest of manipulation. Otherwise it will hard to maintain and update properties and when you do it in that way remove your static methods. and use proper names for each and every method.
This code will give compilation errors because you have called methods in wrong way and you have call method2 and method5 within static method.

in method2() you have given 4 parameter but you are not using even a single parameter because you are getting from user.
like your modified code is
import java.util.Scanner;
public class cs21`enter code here`0 {
public static double weight;
public static double height;
public static double bmi;
public double wcal;
public double mcal;
public static double age;
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
cs210 cs=new cs210();
method1 ();
double val=cs.method2 ();
double value1=cs.method3 (weight,age,height);
double value2=cs.method4 (weight,age,height);
cs.method5 (bmi,value1,value2);
}
public static void method1 () {
System.out.println ("This program implements a Health Assistance Calculator ");
System.out.println ("Given a weight, height, and age, it will compute:\n");
System.out.println ("BMI - Body Mass Index");
System.out.println ("Calories needed per day to maintain weight");
}
public double method2 () {
Scanner keyboard = new Scanner (System.in);
System.out.println ("Please enter your weight:");
weight = keyboard.nextDouble ();
System.out.println ("Press 1 if weight was entered in Kg \n Press 2 if weight was entered in Lbs");
double wunits = keyboard.nextDouble();
if (wunits == 1) {
System.out.println("Thank you");
} else if (wunits == 2){
weight = weight / 2.2;
System.out.println("Thank you");
}
else {
System.out.println ("Please try again");
return 0;
}
System.out.println("Please enter your height:");
height = keyboard.nextDouble ();
System.out.println ("Press 1 if height was entered in meters \n Press 2 if height was entered in inches");
int hunits = keyboard.nextInt();
if(hunits ==1) {
System.out.println("Thank you");
} else if (hunits == 2){
height = height / 0.0254;
}else {
System.out.println("Please try again");
return 0;
}
System.out.println("Please enter your age in years:");
age = keyboard.nextDouble ();
bmi = weight / Math.pow(height, height);
return ( bmi + age + height + weight);
}
public static double method3(double weight, double age, double height) {
double paf = 1.375;
double mcal;
mcal = (13.397 * weight + 4.799 * height + 5.677 * age + 88.362) * paf;
return mcal;
}
public static double method4(double weight, double age, double height){
double wcal;
double paf=1.375;
wcal = (93247 * weight + 3.098 * height - 4.330 * age + 447.593) * paf;
return wcal;
}
public void method5(double bmi, double mcal, double wcal){
System.out.println("Your BMI is:" + bmi);
System.out.println("A BMI in the range of 18.5 to 24.9 is considered normal\n");
System.out.println("To maintain your current weight:");
System.out.println("Men need" + mcal + "per day");
System.out.println("Women need" + wcal + "per day");
}
}

Actually to make your code work the way it is written you should:
make all the fields and methods static
remove parameters from all methods declarations
declare local variable paf in method4.
That being said the code in that form is quite ugly. You should think about the following improvements:
class name should start from capital letter
class name should be something meaningful (e.g. BcmCalculator)
fields should be private
method should have meaningful names ( printGreetings, readUsersAttributes, etc)
in main method you should create instance of the class and call its methods
paf should be a constant (ie field private static final double PAF = 1.375;).
There are further possible improvements, but this should be enough for the beginning.

BMI calculator errors

While doing an assignment for a BMI calculator I keep running into problems with the compiler and the method being used.
The assignment requires me to call a function double bmi to calculate the bmi. I am having problems getting the calling of the function correct. Any help would be great.
One of the errors:
Prog5.java:44: error: illegal start of expression
public static double calculateBmi(double height, double total) {
^
Code:
import java.util.Scanner;
public class Prog5 {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
double avgweight,bmi,total,wReading;
int heightft,heightin,height,k;
String category,weightreading;
System.out.print("Enter the height(in feet and inches separated by spaces): ");
heightft = sc.nextInt();
heightin = sc.nextInt();
height = ((heightft*12)+heightin);
System.out.print("Enter the weight values separated by spaces followed by a negative number: ");
wReading = sc.nextDouble();
While (wReading >=0);
{
total = wReading+total;
Count++;
wReading = sc.nextDouble();
}
avgweight = 0;
total = 0;
weightreading = "Weight readings: " + wReading;
avgweight = total/Count;
public static double calculateBmi(double height, double total) {
{
double bmi = 0;
double total = 0;
double height = 0;
bmi = (height*703) / (total*total);
}
return bmi;
}
if ( bmi > 30)
category=("Obese");
else if (bmi >= 25)
category=("Overweight");
else if (bmi >= 18.5)
category=("Normal");
else {
category=("Underweight");
}
System.out.println("");
System.out.println("Height: "+ heightft + " feet " + heightin + " inches" );
System.out.println("Weight readings: "+ count);
System.out.println("Average weight: " + avgweight + "lbs");
System.out.println("");
System.out.printf("BMI: " + "%.2f", bmi);
System.out.println("");
System.out.println("Category: " + category);
System.out.println("");
}
private static void ElseIf(boolean b) { }
private static void If(boolean b) { }
}

The problem you mention is due to you beginning another method inside main. You instead want a structure something like:
public class Prog5
{
public static void main(String[] args)
{
// code here
}
public static double calculateBMI(double height, double total)
{
//other code
}
}

Your problem is that you are attempting to define a method (namely, public static double calculateBMi) inside a method (public static void main), and Java does not let you do that. (Basically, methods that aren't main need to be attached to a class.)
In the future, you may want to look around before asking this kind of question, since duplicate versions of this have been asked. Your question is basically: Function within a function in Java

return issue for method

I am having an issue with a method returning to the main method. It is saying that amount in "return amount" cannot be resolved to a variable. Where am I off on this??
This is the message I get:
Multiple markers at this line
- Void methods cannot return a
value
- amount cannot be resolved to a
variable
Here is the code:
import java.util.Scanner;
public class Investment {
public static void main(String[]args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter the amount invested: ");
double amount = input.nextDouble();
System.out.print("Enter the annual interest rate: ");
double interest = input.nextDouble();
int years = 30;
System.out.print(futureInvestmentValue(amount, interest, years)); //Enter output for table
}
public static double futureInvestmentValue(double amount, double interest, int years) {
double monthlyInterest = interest/1200;
double temp;
double count = 1;
while (count < years)
temp = amount * (Math.pow(1 + monthlyInterest,years *12));
amount = temp;
System.out.print((count + 1) + " " + temp);
}
{
return amount;
}
}

You curly braces are not correct. The compiler - and me - was confused about that.
This should work (at least syntactically):
import java.util.Scanner;
public class Investment {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter the amount invested: ");
double amount = input.nextDouble();
System.out.print("Enter the annual interest rate: ");
double interest = input.nextDouble();
int years = 30;
System.out.print(futureInvestmentValue(amount, interest, years));
}
public static double futureInvestmentValue(
double amount, double interest, int years) {
double monthlyInterest = interest / 1200;
double temp = 0;
double count = 1;
while (count < years)
temp = amount * (Math.pow(1 + monthlyInterest, years * 12));
amount = temp;
System.out.print((count + 1) + " " + temp);
return amount;
}
}

Remove amount from its own scope As a start. Also from the method futureInvestmentValue, you take in amount as an argument but the value is never modified so you're returning the same value being passed which is most likely not the desired outcome.

remove return amount from its own scope
the method futureInvestmentValue... You can't modify any of the parameters inside the method so you have to declare another variable besides amount inside the method (maybe it's the temp variable you keep using) and return that instead
when you return something, the return statement is always inside the method. Never outside it while inside its own braces (never seen this before...)
import java.util.Scanner;
public class Investment {
public static void main(String[]args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter the amount invested: ");
double amount = input.nextDouble();
System.out.print("Enter the annual interest rate: ");
double interest = input.nextDouble();
int years = 30;
System.out.print(futureInvestmentValue(amount, interest, years)); //Enter output for table
}
public static double futureInvestmentValue(double amount, double interest, int years) {
double monthlyInterest = interest/1200;
double temp;
double count = 1;
while (count < years) {
temp = amount * (Math.pow(1 + monthlyInterest,years *12));
System.out.print((count + 1) + " " + temp);
}
return amount;
}
}