CST141 Project 7: Chapter 13

Shape and Parallelogram Classes
--or--
Employee, SalesPerson and Executive Classes,
and SalaryConstants Interface

• Open the "shapes" project from the "Abstract Classes and Interfaces" download and modify it by adding a new final class Parallelogram as follows (this is a partial credit assignment for up to 7½ out of ten (10) points):
   

                 

  • Three instance variables including side1 and side2 both which must be zero (0) or greater, plus angle, the angle of two opposite corners which must be between zero (0) and 179; default is zero (0) for all fields
  • The no-argument constructor only contains a call to the this constructor with default values for the data fields all of which are zero (0)
  • The Parallelgram(int, int, int, int, int) constructor initializes the data fields by calling the super class constructor for the x and y fields and the set methods of this class for side1, side2 and angle
  • Write set (following the class data validation rules specified above) and get method for all data fields
  • Write getAngle2() method that returns the value of the other angle of the parallelogram which is calculated as 180 minus the first angle
  • Write a method draw() that overrides the abstract method in Shape and that prints the two sides and two angles of the parallelogram (preceded by the position of the Shape object) to the terminal window in the format:

    Position at x = 20, y = 0
Draw parallelogram with sides 10 by 15 and angles 60 degrees and 120 degrees

• Draw the UML diagram for the Parallelogram; it is suggested that you do this before you begin to create the class as this should make the coding much easier
   
• Update the main() method in the "Shapes.java" class file to instantiate a fourth element to the s array from the Parallelogram constructor

• Document the program using the Javadoc standard by:

1. Including a substantive comment statement that describes the class's purpose, as well as substituting your name for the existing @author comment and the assignment due date for the @version comment that already exist at the top of the new class
2. Entering a substantive comment before each method (including the constructor) to describe its function along with @parameter and @return tags

• Create a new project named "project-7" with three class files (an abstract superclass and two final subclasses) and an interface file as per the following specifications (this is the full credit assignment for up to 10 out of ten (10) points):

• Specifications for abstract superclass Employee:

1. The class should have one constructor that takes three arguments, one for each of its attributes, and passes those values to the set methods
2. A set method for each of the three instance variables; follow validation rules for the salary attribute (see above) and throw an Exception for invalid data
3. A get method for each of the three instance variables
4. An abstract method getAdditionalIncome() of type double
5. Method getTotalSalary() of type double that returns the sum of the salary attribute and the return value of the getAdditionalIncome() method (see SalesPerson and Executive class descriptions below) of its subclasses
6. Method toString() returns a "string representation of an Employee object with values preceded by descriptive labels as follows: (a) each of the three instance variables; and (b) the return value from the getTotalSalary() method

• Specifications for final subclass Salesperson:

1. The class should have two constructors: (a) one that takes no arguments and passes the default values to the second constructor via the this reference; and (b) another that takes four arguments, one its own sales attribute and the three others for its superclass; it passes the three arguments to the superclass' constructor and passes the sales argument to to its own set method
2. A set method for the sales instance variable; follow validation rules in the set method (see above) and throw an Exception for invalid data
3. A get method for the sales instance variable
4. Method getAdditionalIncome() of type double that "implements" the abstract method from superclass Employee and  returns a salesperson's commission which is calculated by multiplying the sales attribute times the sales commission rate constant that comes from the SalaryConstants interface (see below)
5. There is no toString() method since output for the commission is handled in the toString() method of the superclass

• Specifications for final subclass Executive:

1. The class should have two constructors: (a) one that takes no arguments and passes the default values to the second constructor via the this reference; and (b) another that takes three arguments which it passes to the superclass constructor
2. Method getAdditionalIncome() of type double that "implements" the abstract method from superclass Employee and returns a executive's bonus which is calculated by multiplying the salary attribute from the superclass Employee times the bonus rate constant that comes from the SalaryConstants interface (see below)
3. There is no toString() method since output for the bonus is handled in the toString() method of the superclass

• In the interface SalaryConstants define the following constants:

• COMMISSION_RATE of type double assigned the value 0.15 (15%)
• BONUS_RATE of type double assigned the value 0.40 (40%)

• Draw UML diagrams for the Employee, Salesperson and Executive classes; it is suggested that you do this before you begin to create the class as this should make the coding much easier
   
• Select one of the three options below for writing a test (driver) class named "Main.java" based on the superclass, subclasses and interface files:

• Write a driver class similar to "Shapes1.java" from the Chapter 15 lectures that instantiates one object from each subclass, Salesperson and Executive, and displays the return value of the toString() method of the objects using either System.out.println() or JOptionPane.showMessageDialog() (8½ points maximum)
   
• Write a driver class similar to "Shapes2.java" from the Chapter 15 lectures that instantiates one object from each subclass (Salesperson and Executive) as array objects of super type Employee using subtyping, and iterates through the array elements to display the return value of the toString() method of the objects using either System.out.println() or JOptionPane.showMessageDialog() (9 points maximum)
   
• Full credit  Write a driver class that instantiates one object from each subclass (Salesperson and Executive) as array objects of super type Employee using subtyping calling their no-parameter constructors; then iterate through the array of objects to input values for each of the four fields using either a Scanner object or JOptionPane.showInputDialog() (and an appropriate parse method for numeric fields) and pass the input values to the set methods of each of the instance variables
• It will be necessary to use Java's instanceof operator for the Salesperson object to get input from the user only for the sales field of this object and not Executive; in addition it will be necessary in the call to the set method for sales to cast the object to type Salesperson as per the following:
  ( (Salesperson) employee[index] )
  
• Still inside the loop call the toString() method of both objects to display the values using using either System.out.println() or JOptionPane.showMessageDialog() (10 points maximum)

• Document the program using the Javadoc standard by:

1. Including a substantive comment statement that describes the class's or interface's purpose, as well as substituting your name for the existing @author comment and the assignment due date for the @version comment that already exist at the top of each new class
2. Entering a substantive comment before each method (including the constructor) to describe its function along with @parameter, @return and @throws tags

• When all steps are finished, you will submit all Java files and UML diagrams as follows:
   
  • The Shape and Parallelogram Classes assignment:
     
    1. The "Parallelogram.java" subclass
    2. The "Shapes1.java" file with the first "test" program
    3. The "Shapes2.java" file with the second "test" program (if you do this one)
    4. The UML diagram for the Parallelogram class
        
  • The Employee, SalesPerson and Executive Classes, and SalaryConstants Interface assignment:
     
    1. The "Employee.java" superclass
    2. The "Salesperson.java" subclass
    3. The "Executive.java" subclass
    4. The "SalaryConstants.java" interface
    5. The "Main.java" driver class
    6. The UML diagrams for the Employee, Salesperson and Executive classes
        
• Students may work on all projects in teams of two or three, and, if so, all students in the group must submit the same project to their own dropboxes in Blackboard.  In the text box's dropbox, as well as in the source code documentation (comments), state the name(s) of the classmate(s) with whom you worked.
   
• The completed project with a copy of all files (the .java files) along with the UML diagrams submitted electronically via attachments to a Blackboard dropbox is due to Prof. Struck by 11:59 p.m. on the date specified in the course outline.