Constructors and displaying data from private fields

I have to write a program with the following information:

Write a class Employee with the following specifications:

Fields:
private First name
private Last name
private Age
private Annual Income

Constructor:

Write a constructor which takes four parameters corresponding to the four fields and assigns them to the fields.

Methods:

A method which computes the net annual pay: subtract 7% medical, 3% insurance.

A method to display all information

Create a main class EmployeeExample which creates two employee objects. Use your own data.

I successfully created a method in which the annual net salary is computed and I can display that information for each employee. However, I haven't a clue on how to display the information found in the constructor, i.e, last name, first name, age, etc.

Here is my code:

Code:

---


//create EmployeeExample class
public class EmployeeExample
{
    //Create main method
    public static void main(String [] args)
    {
        //create constructors for employee1 and employee 2
        Employee emp1 = new Employee("George", "Harrison", 100000, 45);
        Employee emp2 = new Employee("Ringo", "Starr", 110000, 46);
        //display output
        System.out.println(emp1.getNetIncome());
        System.out.println(emp2.getNetIncome());
        }
 }
 //create Employee class
 class Employee
 {
    //create variables
    private String firstName;
    private String lastName;
    private double annualIncome;
    private int age;
    //create constructor and arguments
    Employee(String fn, String ln, double ai, int ag)
    {
        firstName = fn;
        lastName = ln;
        annualIncome = ai;
        age = ag;
    }
    //create method to get annual net income
    double getNetIncome()
    {
        double medical = annualIncome * 0.07;
        double insurance = annualIncome * 0.03;
        double annualNetIncome = annualIncome - medical - insurance;
        return (annualNetIncome);
    }
 }

---

I'm not sure what to do to display the last name, first name, etc. I tried putting emp1.firstName, et., into my System.out.println statement, but of course it doesn't recognize it since it is private and in another class. I also tried using emp1.ln but that didn't work either. I then attempted to add the variables into the getNetIncome() method and when that didn't work I tried using the constructor arguments in the getNetIncome() method but that didn't work either.

Please advise as I am out of ideas.

You write the method in the Employee class. Since the method and private variables are in the same class you have direct access to them. So just use them in your print statements.

Quote:

---

Originally Posted by Junky

You write the method in the Employee class. Since the method and private variables are in the same class you have direct access to them. So just use them in your print statements.

---

If that is the case then what is this used for?

Code:

---


Employee(String fn, String ln, double ai, int ag)
{
    firstName = fn;
    lastName = ln;
    annualIncome = ai;
    age = ag;
}

---

I thought the reason for defining these arguments was because the variables were private and so had to be called some how by using the fn, ln, ai, and ag.

The parameters to a method or constructor have nothing to do with the accessibilty of the class variables. Other than if the variable is private then access can only be made via a setter.

Code:

---

class Foo {
    private int value = 100;

    public void doStuff(int divisor) {
        System.out.println(value / divisor);
    }
}

---

It makes no difference to the output of the method if the variable value is public, protected or private.

Ok. Thank you. I'm going to have to chew on this a while. I appreciate your help.

I figured it out. Or at least it works anyway.

Code:

---


//create EmployeeExample class
public class EmployeeExample
{
    //Create main method
    public static void main(String [] args)
    {
        //create constructor for employee 1
        Employee emp1 = new Employee("George ", "Harrison ", 100000, 45);

        //output for employee 1
        emp1.display();
        System.out.println("Net income: " + emp1.getNetIncome() + "\n");

        //create constructor for employee 2
        Employee emp2 = new Employee("Ringo", "Starr", 110000, 46);

        //output for employee 1
        emp2.display();
        System.out.println("Net income: " + emp2.getNetIncome());
    }
 }
 //create Employee class
 class Employee
 {
    //create variables
    private String firstName;
    private String lastName;
    private int age;
    private double annualIncome;

    //create constructor and arguments
    Employee(String fn, String ln, double ai, int ag)
    {
        firstName = fn;
        lastName = ln;
        annualIncome = ai;
        age = ag;
    }
    //create display method to print information
    void display()
    {
        System.out.println("First name: " + firstName);
        System.out.println("Last name: " + lastName);
        System.out.println("age: " + age);
        System.out.println("Gross income: " + annualIncome);
    }
    //create method to get annual net income
    double getNetIncome()
    {
        double medical = annualIncome * 0.07;
        double insurance = annualIncome * 0.03;
        double annualNetIncome = annualIncome - medical - insurance;
        return (annualNetIncome);
    }
 }

---

Once again, thank you for the help.