employee

class Employee {
        private String name;
        private String employeeID;
        private String hireDate;

        public void setName(String name) {
                this.name = name;
        }
        public String getName() {
                return this.name;
        }
        public void setNumber(String employeeID) {
                this.employeeID = employeeID;
        }
        public String getNumber() {
                return this.employeeID
                        .matches("(?i)^[0-9]{3}-[A-M]{1}$") ?
                                this.employeeID : "Invalid employee ID! Format must be XXX-L.";
                /* "(?i)" -> case-insensitive, aka ignore case
                   "^" -> emphasizes String start
                   "[0-9]{3}" -> must match XXX, where X is a digit 0-9
                   "-" -> 3 digit code must be followed by a hyphen
                   "[A-M]{1}" -> following the hyphen, must be a single letter, A-M
                   "$" -> emphasizes String end

                   Method uses ternary operator, below is the translation:

                   if (employeeID.matches(regex)) {
                        return employeeID;
                   } else {
                        return ""; // some String
                   }
               */
        }
        public void setHire(String hireDate) {
                this.hireDate = hireDate;
        }
        public String getHire() {
                return this.hireDate;
        }

        // Default no-args constructor
        public Employee() {

        }
        // Overloaded constructor with 3 parameters
        public Employee(String name, String employeeID, String hireDate) {
                this.name = name;
                this.employeeID = employeeID;
                this.hireDate = hireDate;
        }

}
class ProductionWorker extends Employee {
        private int shift;
        private double wage;

        public void setShift(int shift) {
                this.shift = shift;
        }
        public int getShift() {
                return this.shift;
        }
        public void setPayRate(double wage) {
                this.wage = wage;
        }
        public double getPayRate() {
                return this.wage;
        }

        //Default no-args constructor
        public ProductionWorker() {

        }
        // Overloaded constructor with 3 parameters
        public ProductionWorker(String name, String employeeID, String hireDate) {
                // Call constructor from superclass (Employee)
                super(name, employeeID, hireDate);
        }
}