Payroll System

[David Tran]

Assume the employees' names, salary, base salary, commission rate, hourly rate are already entered into the system (from the database, for example). You run this program weekly to enter the data depending on the employee's position:
Salarid employee: No data to be entered.
Commission employee: Enter the amount of gross sales.
Base plus commission employee: Enter the amount of gross sales.
Hourly employee: Enter the hours worked.
You are required to write a GUI program instead of a console program.
For this assignment you should add an abstract method, e.g. enterData into the superclass Employee, and override it in each of its subclasses. To test, create an array of Employees. Loop through the array to enter data. Then loop through the array again to calculate and output their earnings. Here are the detailed steps:

1/ Copy Employee.java and its 4 subclasses into a folder Assign9. In Eclipse create a project on this folder.
2/ Create a new class Assign with public static void main(String[] args)
3/ In Employee.java, add public abstract void enterData();
4/ Implement the method enterData() in the class SalariedEmployee, CommissionEmployee, and HourlyEmployee. You don't have to implement it in BasePlusCommissionEmployee. It should input data by calling JOptionPane.showInputDialog() with the specific prompt, and call the corresponding setGrossSales() or setHours().
5/ In Assign main() method, create an array of Employee. Construct the 4 subclass objects as did in PayrollSystemTest.java except that the sales or hours should be zero. Store them into the array.
6/In a loop through the array, call employee.enterData();
7/ After all data are entered, loop through the array again and output the payroll by calling employee.toString() and employee.earnings()
8/Append the output into a String, and call JOptionPane.showMessageDialog() after the loop.

I'm done with 1,2,3, but the rest i can't figue it out. Can someone help me?

public class Assign
{
   public static void main(String[] args) 
   {
      // create subclass objects
      SalariedEmployee salariedEmployee = 
         new SalariedEmployee("John", "Smith", "111-11-1111", 800.00);
      HourlyEmployee hourlyEmployee = 
         new HourlyEmployee("Karen", "Price", "222-22-2222", 16.75, 40);
      CommissionEmployee commissionEmployee = 
         new CommissionEmployee(
         "Sue", "Jones", "333-33-3333", 10000, .06);
      BasePlusCommissionEmployee basePlusCommissionEmployee = 
         new BasePlusCommissionEmployee(
         "Bob", "Lewis", "444-44-4444", 5000, .04, 300);

      System.out.println("Employees processed individually:");
      
      System.out.printf("%n%s%n%s: $%,.2f%n%n", 
         salariedEmployee, "earned", salariedEmployee.earnings());
      System.out.printf("%s%n%s: $%,.2f%n%n",
         hourlyEmployee, "earned", hourlyEmployee.earnings());
      System.out.printf("%s%n%s: $%,.2f%n%n",
         commissionEmployee, "earned", commissionEmployee.earnings());
      System.out.printf("%s%n%s: $%,.2f%n%n", 
         basePlusCommissionEmployee, 
         "earned", basePlusCommissionEmployee.earnings());

      // create four-element Employee array
      Employee[] employees = new Employee[4]; 

      // initialize array with Employees
      employees[0] = salariedEmployee;
      employees[1] = hourlyEmployee;
      employees[2] = commissionEmployee; 
      employees[3] = basePlusCommissionEmployee;
    
      
   } // end main
} // end class Assign

public abstract class Employee 
{
   private final String firstName;
   private final String lastName;
   private final String socialSecurityNumber;

   // constructor
   public Employee(String firstName, String lastName, 
      String socialSecurityNumber)
   {
      this.firstName = firstName;                                    
      this.lastName = lastName;                                    
      this.socialSecurityNumber = socialSecurityNumber;         
   } 

   // return first name
   public String getFirstName()
   {
      return firstName;
   } 

   // return last name
   public String getLastName()
   {
      return lastName;
   } 

   // return social security number
   public String getSocialSecurityNumber()
   {
      return socialSecurityNumber;
   } 

   // return String representation of Employee object
   @Override
   public String toString()
   {
      return String.format("%s %s%nsocial security number: %s", 
         getFirstName(), getLastName(), getSocialSecurityNumber());
   } 

   // abstract method must be overridden by concrete subclasses
   public abstract double earnings(); // no implementation here
   public abstract void enterData();
} // end abstract class Employee

public class HourlyEmployee extends Employee 
{
   private double wage; // wage per hour
   private double hours; // hours worked for week

   // constructor
   public HourlyEmployee(String firstName, String lastName,
      String socialSecurityNumber, double wage, double hours)
   {
      super(firstName, lastName, socialSecurityNumber);

      if (wage < 0.0) // validate wage
         throw new IllegalArgumentException(
            "Hourly wage must be >= 0.0");

      if ((hours < 0.0) || (hours > 168.0)) // validate hours
         throw new IllegalArgumentException(
            "Hours worked must be >= 0.0 and <= 168.0");

      this.wage = wage;
      this.hours = hours;
   } 

   // set wage
   public void setWage(double wage)
   {
      if (wage < 0.0) // validate wage
         throw new IllegalArgumentException(
            "Hourly wage must be >= 0.0");

      this.wage = wage;
   } 

   // return wage
   public double getWage()
   {
      return wage;
   } 

   // set hours worked
   public void setHours(double hours)
   {
      if ((hours < 0.0) || (hours > 168.0)) // validate hours
         throw new IllegalArgumentException(
            "Hours worked must be >= 0.0 and <= 168.0");

      this.hours = hours;
   } 

   // return hours worked
   public double getHours()
   {
      return hours;
   } 

   // calculate earnings; override abstract method earnings in Employee
   @Override                                                           
   public double earnings()                                            
   {                                                                   
      if (getHours() <= 40) // no overtime                           
         return getWage() * getHours();                                
      else                                                             
         return 40 * getWage() + (getHours() - 40) * getWage() * 1.5;
   }                                          

   // return String representation of HourlyEmployee object              
   @Override                                                             
   public String toString()                                              
   {                                                                     
      return String.format("hourly employee: %s%n%s: $%,.2f; %s: %,.2f",
         super.toString(), "hourly wage", getWage(),                     
         "hours worked", getHours());                                   
   }             
   public void enterData(){
	   JOptionPane.showInputDialog("Please enter:");
   }
} // end class HourlyEmployee

public class SalariedEmployee extends Employee 
{
   private double weeklySalary;

   // constructor
   public SalariedEmployee(String firstName, String lastName, 
      String socialSecurityNumber, double weeklySalary)
   {
      super(firstName, lastName, socialSecurityNumber); 

      if (weeklySalary < 0.0)
         throw new IllegalArgumentException(
            "Weekly salary must be >= 0.0");

      this.weeklySalary = weeklySalary;
   } 

   // set salary
   public void setWeeklySalary(double weeklySalary)
   {
      if (weeklySalary < 0.0)
         throw new IllegalArgumentException(
            "Weekly salary must be >= 0.0");

      this.weeklySalary = weeklySalary;
   } 

   // return salary
   public double getWeeklySalary()
   {
      return weeklySalary;
   } 

   // calculate earnings; override abstract method earnings in Employee
   @Override                                                           
   public double earnings()                                            
   {                                                                   
      return getWeeklySalary();                                        
   }                                             

   // return String representation of SalariedEmployee object   
   @Override                                                    
   public String toString()                                     
   {                                                            
      return String.format("salaried employee: %s%n%s: $%,.2f",
         super.toString(), "weekly salary", getWeeklySalary());
   } 
   public void enterData(){
	    JOptionPane.showInputDialog("Please enter the hours worked by hourly employee:");
	   
   }
} // end class SalariedEmployee

public class CommissionEmployee extends Employee 
{
   private double grossSales; // gross weekly sales
   private double commissionRate; // commission percentage

   // constructor
   public CommissionEmployee(String firstName, String lastName, 
      String socialSecurityNumber, double grossSales, 
      double commissionRate)
   {
      super(firstName, lastName, socialSecurityNumber);

      if (commissionRate <= 0.0 || commissionRate >= 1.0) // validate 
         throw new IllegalArgumentException(
            "Commission rate must be > 0.0 and < 1.0");

      if (grossSales < 0.0) // validate
         throw new IllegalArgumentException("Gross sales must be >= 0.0");

      this.grossSales = grossSales;
      this.commissionRate = commissionRate;
   } 

   // set gross sales amount
   public void setGrossSales(double grossSales)
   {
      if (grossSales < 0.0) // validate
         throw new IllegalArgumentException("Gross sales must be >= 0.0");

      this.grossSales = grossSales;
   } 

   // return gross sales amount
   public double getGrossSales()
   {
      return grossSales;
   } 

   // set commission rate
   public void setCommissionRate(double commissionRate)
   {
      if (commissionRate <= 0.0 || commissionRate >= 1.0) // validate
         throw new IllegalArgumentException(
            "Commission rate must be > 0.0 and < 1.0");

      this.commissionRate = commissionRate;
   } 

   // return commission rate
   public double getCommissionRate()
   {
      return commissionRate;
   } 

   // calculate earnings; override abstract method earnings in Employee
   @Override                                                           
   public double earnings()                                            
   {                                                                   
      return getCommissionRate() * getGrossSales();                    
   }                                             

   // return String representation of CommissionEmployee object
   @Override                                                   
   public String toString()                                    
   {                                                           
      return String.format("%s: %s%n%s: $%,.2f; %s: %.2f",    
         "commission employee", super.toString(),              
         "gross sales", getGrossSales(),                       
         "commission rate", getCommissionRate());             
   }

@Override
public void enterData() {
	JOptionPane.showInputDialog("Please enter the gross sales by comission employee:");
	
} 
} // end class CommissionEmployee

public class BasePlusCommissionEmployee extends CommissionEmployee 
{
   private double baseSalary; // base salary per week

   // constructor
   public BasePlusCommissionEmployee(String firstName, String lastName, 
      String socialSecurityNumber, double grossSales,
      double commissionRate, double baseSalary)
   {
      super(firstName, lastName, socialSecurityNumber, 
         grossSales, commissionRate);

      if (baseSalary < 0.0) // validate baseSalary                  
         throw new IllegalArgumentException("Base salary must be >= 0.0");
            
      this.baseSalary = baseSalary;                
   }

   // set base salary
   public void setBaseSalary(double baseSalary)
   {
      if (baseSalary < 0.0) // validate baseSalary                  
         throw new IllegalArgumentException("Base salary must be >= 0.0");
            
      this.baseSalary = baseSalary;                
   } 

   // return base salary
   public double getBaseSalary()
   {
      return baseSalary;
   }

   // calculate earnings; override method earnings in CommissionEmployee
   @Override                                                            
   public double earnings()                                             
   {                                                                    
      return getBaseSalary() + super.earnings();                        
   } 

   // return String representation of BasePlusCommissionEmployee object
   @Override                                                           
   public String toString()                                            
   {                                                                   
      return String.format("%s %s; %s: $%,.2f",                       
         "base-salaried", super.toString(),                            
         "base salary", getBaseSalary());                             
   } 
} // end class BasePlusCommissionEmployee

[Stephan van Hulst]

Hi David,

After you enter a value in the input dialog, the showInputDialog() method returns and gives you the input in String form. You can parse this and then perform the appropriate action on that data.

What specifically don't you understand?

I'm also breaking up your code to show the separate classes.

[David Tran]

I don't understand in step 4 that is call the corresponding setGrossSales() or setHours(). And In a loop through the array, call employee.enterData();

[Stephan van Hulst]

Well, each employee has an enterData() method, in which you should prompt the user to fill in the necessary data to determine the earnings of an employee.

That means that an hourly employee should prompt the user to fill in the amount of hours that employee works, after which it parses the value and passes it to the setHours() method. Do similar things for the other types of employees.

In the Assign class you have an array of employees. You can use the (enhanced) for-loop to perform an action for each employee in the array, which in this case is calling the enterData() method.