Os Stewart

Keith Lynn wrote:Are you sure the .class file of your program is in the CLASSPATH and that the class has a main method?

I think so, The file works for me, but when my friend tries it, it does not work.

package payroll; import javax.swing.JOptionPane; public class Payroll { public static void main(String[] args) { String grossSalaryString, numberDependentString; double grossSalary, federalTax, stateTax, dependentDeduction, totalWithholding, netSalary; int numberDependent; //Input Gross Salary grossSalaryString = JOptionPane.showInputDialog("Welcome, Please enter Gross Salary:"); //Input number of Dependents numberDependentString = JOptionPane.showInputDialog("Please Enter the number of dependents:"); //Convert salary string to double grossSalary = Double.parseDouble(grossSalaryString); //Convert dependent string to double numberDependent = Integer.parseInt(numberDependentString); //Calculate federal tax federalTax = grossSalary * 0.28; //Calculate state tax stateTax = grossSalary * 0.065; //Calculate dependent deduction dependentDeduction = (numberDependent * 0.025) * grossSalary; //Calculate total withholding totalWithholding = federalTax + stateTax - dependentDeduction; //Calculate net salary netSalary = grossSalary - totalWithholding; //Print out result System.out.println("Salary: $" + grossSalary); System.out.println("Dependents: $" + dependentDeduction); System.out.println("State Tax: $" + stateTax); System.out.println("Federal Tax: $" + federalTax); System.out.println("Total Take-Home Pay: $" + netSalary); System.exit(0); } }

Can someone let me know what I can do to fix the error:

Error: Could not find or load main class

Stefan Evans wrote:

It shouldn't be saved in sum?

Correct. If what you are calculating is the federal tax, then it should be saved into the variable for federal tax.
And then on the next line where you print it out, it will print out the correct value.
The reason it is printing 0 right now, is that you did the calculation for it BEFORE the user entered in the data.


// Calculate federal tax here. federalTax= salary * 0.065; System.out.println("Federal Tax: $" + federalTax);

I actually don't understand what the "sum" variable represents.
All of the other variables are named well, but this one is a mystery to me.
Do you need it? What does it represent? Maybe you can name it better?
Also note that you have two variables:

public static boolean Sum; double sum = 0;

Sum with a capital S and sum with a lower case s. That also caused me some confusion.

Okay, the sum is suppose to be the salary and dependents multiplied total.

Liutauras Vilda wrote:Here is what you have at the moment:
double salary = 0; double numDependents = 0; double sum = 0; double dependentDeduction = salary * 0.025 * numDependents; double stateTax = salary * 0.065; double federalTax = salary * 0.28; double totalWithholding = stateTax + federalTax; double takeHomePay = salary - stateTax - federalTax + dependentDeduction;
As you see at the beginning you initialize "salary", "numDependents", "sum" with 0 (it is fine so far).
Then, on the lines below you do some calculations and assign variables with results.
So, "dependentDeduction", "stateTax", "federalTax", "totalWithholding", "takeHomePay" you get 0 too (not what you want).

The point is, that you using those variables mentioned two lines above in your later calculations and you get I believe not what you think you should get.

So how do I fix it? My original code the, the variables I did not add the "= 0" to, and it did not work at all. I don't know how to fix the variables, that is my problem.

Stefan Evans wrote:Ok, when I run it I just see a bunch of $0 printed out.


Enter Employee name: Stefan Enter Salary: 100000 Enter number of dependents: 2 false State Tax: $0.0 Federal Tax: $0.0 Total Withholdings: $0.0 Take Home Pay: $0.0

Here is a snippet of some of your code:
// Calculate federal tax here. sum = salary * 0.065; // multiply numbers System.out.println("Federal Tax: $" + federalTax);

I read this code as:
multiply salary by the federal tax rate, and save it in the variable "sum"
print out the value of the variable "federal tax"

When I put it like that, do you see any problems with it?

It shouldn't be saved in sum?

I don't get any of this. I don't understand what to do to fix it or how. I know where it's going wrong, but I don't get how. I need to step away from looking at this, because my brain is not understanding this right now.

package payroll; import java.util.Scanner; class Payroll { public static boolean Sum; public static void main(String args[]) { Scanner input = new Scanner(System.in ); String employeeName; double salary = 0; double numDependents = 0; double sum = 0; double dependentDeduction = salary * 0.025 * numDependents; double stateTax = salary * 0.065; double federalTax = salary * 0.28; double totalWithholding = stateTax + federalTax; double takeHomePay = salary - stateTax - federalTax + dependentDeduction; System.out.print("Enter Employee name: "); employeeName = input.nextLine(); System.out.print("Enter Salary: "); salary = input.nextDouble(); System.out.print("Enter number of dependents: "); numDependents = input.nextDouble(); System.out.println(Sum); sum = salary * numDependents; // multiply numbers System.out.println("State Tax: $" + stateTax); // Calculate federal tax here. sum = salary * 0.065; // multiply numbers System.out.println("Federal Tax: $" + federalTax); // Calculate dependant deduction here. sum = salary * 0.28; // multiply numbers System.out.println("Total Withholdings: $" + dependentDeduction); // Calculate total withholding here. sum = stateTax * federalTax; System.out.println("Take Home Pay: $" + takeHomePay); //Calculate take home pay sum = salary - stateTax - federalTax + dependentDeduction; System.exit(0); } }


And there are no errors anymore, but I can't get the salary and dependents to give me a sum. And the State Tax, Federal Tax, Withholdings, and home pay won't generate either. I'm lost. I'm just trying to get this too work to see what the final result will look like.

When I run it, this is what I get:

run:
Enter Employee name: ofelia
Enter Salary: 1500
Enter number of dependents: 2
false
State Tax: $0.0
Federal Tax: $0.0
Total Withholdings: $0.0
Take Home Pay: $0.0
BUILD SUCCESSFUL (total time: 35 seconds)

I thought I had it but I don't. My values are the Salary and number of dependents. I thought?

the printIn (sum) reads false?

Okay, when I compiled it everything inputted fine, but it won't compile the sum of any of the math. Am I missing something here? My math looks right, but it won't total it?

* To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package payroll; import java.util.Scanner; class Payroll { public static boolean Sum; public static void main(String args[]) { /* 1. compile program here to see if didn't miss anything */ Scanner input = new Scanner(System.in ); String employeeName; double salary = 0; double numDependents = 0; double sum = 0; double dependentDeduction = salary * 0.025 * numDependents; double stateTax = salary * 0.065; double federalTax = salary * 0.28; double totalWithholding= stateTax + federalTax; double takeHomePay = salary - stateTax - federalTax + dependentDeduction; /* 2. compile program here to see if it compiles */ System.out.print("Enter Employee name: "); employeeName = input.nextLine(); System.out.print("Enter Salary: "); salary = input.nextDouble(); System.out.print("Enter number of dependents: "); numDependents = input.nextDouble(); System.out.println(Sum); sum = salary * numDependents; // multiply numbers /* 11. compile your code once again */ /* 12. execute your program and print sum out to see if it matches */ /* use System.out.println(sum); */ /* And keep going like this by compiling often enough. */ System.out.println("State Tax: $" + stateTax); // Calculate federal tax here. sum = salary * 0.065; // multiply numbers System.out.println("Federal Tax: $" + federalTax); // Calculate dependant deduction here. sum = salary * 0.28; // multiply numbers System.out.println("Total Withholdings: $" + dependentDeduction); // Calculate total withholding here. sum = stateTax * federalTax; System.out.println("Take Home Pay: $" + takeHomePay); //Calculate take home pay sum = salary - stateTax - federalTax + dependentDeduction; System.exit(0); } }

Campbell Ritchie wrote:

Enos Winder wrote:. . .
Now on the last line you will need a parse.
. . .

You don't need to parse anything in what you wrote. There are two reasons it won't work (probably more):-

1: You are trying to sort out somebody else's code and only correcting part of it.

2: You have salary uninitialised. When you get to the next line, the compiler thinks, “how much is salary? I don't know,” and won't compile any more.

If you can get input via Scanner, use Scanner.

EW: option pane is a very old‑fashioned programming style. It is probably a bad idea to mix console input and GUI input anyway. You seem to be confusing OS by adding things she is unfamiliar with.

Okay, when I started, this code was a mess. I got it from an old text book when I was in school. The lesson was to make it compile and fix the errors. I fixed the error, and the next lesson was to be able to input Salary and the number of Dependents. So I came up with this.

package payroll2; // This program calculates an employee's take home pay. import java.util.Scanner; public class Payroll { private static double sum; private static double salary; private static double dependentDeduction; public static void main(String args[]) { Scanner input = new Scanner(System.in ); { double salary; double numDependents; double dependentDeduction = salary * 0.025 * numDependents; double stateTax = salary * 0.065; double federalTax = salary * 0.28; double totalWithholding= stateTax + federalTax; double takeHomePay = salary - stateTax - federalTax + dependentDeduction; // Calculate state tax here. System.out.print("Enter Employee name: "); input.nextLine(); System.out.print("Enter Salary: ");//prompt salary = input.nextDouble(); // read first number from user System.out.print("Enter number of dependents: "); //prompt numDependents = input.nextDouble(); //read second number form user sum = salary * numDependents; // multiply numbers System.out.println("State Tax: $" + stateTax); // Calculate federal tax here. sum = salary * 0.065; // multiply numbers System.out.println("Federal Tax: $" + federalTax); // Calculate dependant deduction here. sum = salary * 0.28; // multiply numbers System.out.println("Total Withholdings: $" + dependentDeduction); // Calculate total withholding here. sum = stateTax * federalTax; System.out.println("Take Home Pay: $" + takeHomePay); //Calculate take home pay sum = salary - stateTax - federalTax + dependentDeduction; System.exit(0); } } }

My issue that I was having that was that the Salary and Number of Dependents are coming up with the errors, that they "might not have been initialized."

I'm just trying to go on lesson by lesson to try to familiarize myself with the steps to "do the job", sort of speak. As the studies in the book go, more things will be added and so on.

I'm sorry you guys... I'm lost, I'm going to start from the last code with Scanner, and try to work from there. I'm not trying to make a pop up box right now, I'm just trying to understand the "Simple stuff" first. I'm sorry you guys, I'm trying to learn, but unfortunately it's a lot to take in for someone who hasn't done this much before. :-)

Line 18 says that my salary and numDependents might not have been initialized.

Ok this is what I did:

package payroll2; // This program calculates an employee's take home pay. import javax.swing.JOptionPane; public class Payroll { private static double sum; private static double salary; private static double dependentDeduction; public static void main(String args[]) { { double salary; double numDependents; double dependentDeduction = salary * 0.025 * numDependents; double stateTax = salary * 0.065; double federalTax = salary * 0.28; double totalWithholding= stateTax + federalTax; double takeHomePay = salary - stateTax - federalTax + dependentDeduction; // Calculate state tax here. JOptionPane.showInputDialog("Enter Employee name: "); JOptionPane.showInputDialog("Enter Salary: ");//prompt JOptionPane.showInputDialog("Enter number of dependents: "); //prompt sum = salary * numDependents; // multiply numbers JOptionPane.showMessageDialog(null,"State Tax: $/"); sum = salary * 0.065; // multiply numbers JOptionPane.showMessageDialog(null,"Federal Tax: $" + federalTax); // Calculate dependant deduction here. sum = salary * 0.28; // multiply numbers JOptionPane.showMessageDialog(null,"Total Withholdings: $" + dependentDeduction); // Calculate total withholding here. sum = stateTax * federalTax; JOptionPane.showMessageDialog(null,"Take Home Pay: $" + takeHomePay); //Calculate take home pay sum = salary - stateTax - federalTax + dependentDeduction; System.exit(0); } } }

I can not get it to work. My salary and numDependents is still not working. Same errors as before. I've never used this JOptionPane before, so I don't know what to do. I'm just trying to get it to calculate my input from salary and dependents.

Enos Winder wrote:Ok, If I have a piece of code that looks like this:
System.out.println("Get Lost");

I can make this same code look like this:
JOptionPane.showMessageDialog(null,"Get Lost");

Or, I can use JOptionPane to do this:
JOptionPane.showInputDialog("Do you know how to get lost?");

This is what I mean when I say replace

Okay, let me try this...