JAVA

(Employee Hierarchy) In this chapter, you studied an inheritance hierarchy in which class BasePlusCommissionEmployee inherited from class CommissionEmployee. However, not all types of employees are CommissionEmployees. In this exercise, youll create a more general Employeesuperclass that factors out the attributes and behaviors in class CommissionEmployee that are common to all Employees. The common attributes and behaviors for all Employees are firstName, lastName, socialSecurityNumber, getFirstName, getLastName, getSocialSecurityNumber and a portion of method toString. Create a new superclass Employee that contains these instance variables and methods and a constructor. Next, rewrite class CommissionEmployee as a subclass of Employee. Class CommissionEmployee should contain only the instance variables and methods that are not declared in superclass Employee. Class CommissionEmployees constructor should invoke class Employees constructor, and CommissionEmployees toString method should invoke Employees to-String method. Once youve completed these modifications, run the CommissionEmployeeTest and BasePlusCommissionEmployeeTest apps using these new classes to ensure that the apps still display the same results for a CommissionEmployee object and BasePlusCommissionEmployee object, respectively.

(Creating a New Subclass of Employee) Other types of Employees might include Salaried-Employees who get paid a fixed weekly salary, PieceWorkers who get paid by the number of pieces they produce or HourlyEmployees who get paid an hourly wage with time-and-a-half1.5 times the hourly wagefor hours worked over 40 hours.

Create class HourlyEmployee that inherits from class Employee and has instance variable hours (a double) that represents the hours worked, instance variable wage (a double ) that represents the wages per hour, a constructor that takes as arguments a first name, a last name, a social security number, an hourly wage and the number of hours worked, set and get methods for manipulating the hours and wage, an earnings method to calculate an HourlyEmployees earnings based on the hours worked and a toStringmethod that returns the HourlyEmployees String representation. Method setWage should ensure that wage is nonnegative, and setHours should ensure that the value of hours is between 0 and 168 (the total number of hours in a week). Use class HourlyEmployee in a test program.