private boolean isValidEmpNum(){
        
        boolean isValid = false;
        
        if(employeeNumber.length() != 5){
            return false;
        }else{
            if(employeeNumber.charAt(3) != '-')
                return false;
            else{
                if((employeeNumber.charAt(4) >= 'A' && employeeNumber.charAt(4)<='M'))
                    for(int i = 0;i < employeeNumber.length()-2; i++){
                        if(Character.isDigit(employeeNumber.charAt(i)))
                            isValid = true;
                        else
                            return false;
                }
            }
        }
        
        return isValid;
            
    }