interface EmployeeSpec{   //  Declares interface implemented by class Employee
   String getName();
   double getWkPay();
}

public abstract class Employee implements EmployeeSpec
/** Abstract class to represent an Employee.  It may not be instantiated.   */
{
// fields

   protected String name;      /** name of employee */
   protected Date birthDate;   /** employee's date of birth */

/* constructors  -- note that constructors do not have return type!
   Even though this constructor cannot be used to generate objects of
   type Employee, it can be called (via super) in extensions.  */

   public Employee (String emp_name, Date emp_bday){
   /** post: creates Employee object from name and birthdate   */
      name = emp_name;         // initialize fields
      birthDate = emp_bday;
   }

// methods

   public String getName()
   // post: Returns name of Employee
   {  return name;               // return name field }
   
   public int getAge()
   /** post: returns the age of the Employee   */
   {          
      Date today = new Date();   // declares today and set to today's date
            // declare yearDiff and initialize to diff of years
      int yearDiff = (today.getYear() - birthDate.getYear());
      
      if ((today.getMonth() > birthDate.getMonth()) || 
         (today.getMonth() == birthDate.getMonth() && 
                  today.getDay() > birthDate.getDay())){
         return yearDiff;         // already had birthday this year
      } else{                        
         return yearDiff - 1;     // adjust age if not had birthday yet this year
      }
   }
   
   public abstract double getWkPay();  
   /** post: Return weekly pay.  Abstract method that will be overridden in 
   	subclasses.*/
   
   /** Not useful to have a main program to test this class since it may not
   	be instantiated.  */
}