Needs help with code

I was wondering how do I go about adding this to my code?

Now, create public accessor & private modifier methods (gets & sets) in the “Employee.java” file for each of the 4 data
members. Use the following as the error-checking criteria in your modifier (“set”) methods:
- First Name & Last Name: Must have size greater than zero, and size less than or equal to 20.
- Employee Id: Value must be greater than or equal to 1000, but less than or equal to 9999.
- Employee Rate: Must be greater than zero.

public class Employee {

public String firstName;
public String lastName;
private double hourlyRate;
private int employeeId;


private Employee(String first, String last, double hourly, int employeeID)
{
firstName = first;
lastName = last;
hourlyRate = hourly;
employeeId = employeeID;
}


public static void main(String[] args)
{

Employee e = new Employee("John", "Doe", 14.79, 1597);

System.out.println("Name: " + e.firstName + " " + e.lastName);
System.out.println("Hourly: $" + e.hourlyRate);
System.out.println("EmployeeID: " + e.employeeId);
System.out.println(); // This will simply create a blank line

e = new Employee("Sarah", " Dao", 17.55, 2574);

System.out.println("Name: " + e.firstName + " " + e.lastName);
System.out.println("Hourly: $" + e.hourlyRate);
System.out.println("EmployeeID: " + e.employeeId);
System.out.println();
}}

Accessor methods are your get() methods; they allow outside classes to access the private members of another class.

For example:

Code Java:

---

public class ClassA
{
 
   private int number;
 
   public ClassA(int theNumber)
   {
 
      number = theNumber;
 
   }
 
   //Now, we make a get() method for number, because it is private
   //and cannot be accessed by other classes
   public int getNumber()
   {
 
      return number;
 
   }
}

---

Code Java:

---

public class ClassATest
{
 
   public static void main(String[] heeheeNotCallingThisArgs)
   {
 
      ClassA test = new ClassA(5);
 
      int cake = test.number; //This would throw an exception, since number is private
      int otherCake = test.getNumber(); //This works, because getNumber() is public
 
   }
}

---

Now, your modifier methods are your set() methods. I really have no clue why you'd want them to be private; this would mean that there's no way to edit the values in your class. Usually set() methods are public. Here's what a typical set() method looks like (using that previous class):

Code Java:

---

public class ClassA
{
 
   private int number;
 
   public ClassA(int theNumber)
   {
 
      number = theNumber;
 
   }
 
   public int getNumber()
   {
 
      return number;
 
   }
 
   //Now we'll add the modifier (set) method, so that number's value can be changed
   public void setNumber(int newNumber)
   {
 
      number = newNumber;
 
   }
}

---

Code Java:

---

public class ClassATest
{
 
   public static void main(String[] heeheeNotCallingThisArgs)
   {
 
      ClassA test = new ClassA(5);
 
      test.number = 2; //This would throw an exception, since number is private
      test.setNumber(2); //This works, because setNumber() is public
 
   }
}

---

Does that clear things up at all?