Instructions:

Preliminaries

1. Create a new project using the Basic Console Application template and the project name DefiningYourOwnClasses.
2. Create a file called DefiningYourOwnClassesReport.txt, placing it in the docs subfolder of your DefiningYourOwnClasses project.
3. Open your DefiningYourOwnClassesReport.txt file. You will use it to record your answers to the questions in all of the parts of this exercise. Start the report with an appropriate title, your names, the date, and a heading to indicate the beginning of Part 1.
4. Skim this document. Then return to this point.
5. Question: About how many minutes do you think it will take you to complete Part 1 of DefiningYourOwnClasses?
6. Question: What time is it now?

Creating the CVS Module

7. Create a new module for your DefiningYourOwnClasses project, calling the module DefiningYourOwnClasses, spelled just like that.
8. Add your report and the initial contents of your DefiningYourOwnClasses project to your new CVS module.

Documenting the Project

9. Write JavaDoc comments based on the planned behavior of the project. Include all of the required tags. Ensure that you can generate the HTML documentation correctly.

Defining Instantiable Classes

10. Unless otherwise specified, use JOptionPane for all required input and output (I/O) in this project (you are free to use whatever method you prefer for other I/O)..
11. Add an introductory message to the main method. When it is finished, the program will prompt the user for two complex numbers and display the results of various operations on those numbers.
12. Ensure that the program exits gracefully when it finishes.
13. Modify the main method so that it declares and creates a Complex object.
14. Question: Explain why the project won't compile at this point.
15. Using the New Class command from the Project menu, create the Complex class.
    • Make the class public.
    • Generate the default constructor.
    • Do not generate a main method.
    • Add the following methods: void setReal(double theReal), void setImaginary(double theImaginary), double getReal(), and double getImaginary(). They should all be public.
    • Add the following variables (fields): double real and double imaginary. Both should have initial values of 0.0 and be private.
16. Question: Explain why the project won't compile at this point.
17. Add return statements to the get methods (accessors) to return the values of the appropriate fields. At this point your program should compile.
18. Modify the set methods (mutators) so that they change the values of the appropriate fields. Add statements to your main method to test your class.
19. Question: Describe the tests that you used to convince yourself that your class is working.
20. Add methods double getMagnitude and double getArgument that return the values suggested by their names. Do not add any new fields to your class.
21. Question: Describe the tests that you used to convince yourself that your getMagnitude and getArgument methods are working.
22. Add methods void setMagnitude( double theMagnitude ) and void setArgument( double theArgument ) that change the real and imaginary components of the Complex object so that the indicated property is set, but the other property is not changed.
23. Question: If you execute x.setMagnitude( someValue ) and then immediately execute x.getMagnitude(), you could get back something slightly different from someValue. Find such a value and explain why this happens.
24. Add methods void add( Complex addend ) and void subtract( Complex subtrahend ) that change the real and imaginary components in the way suggested by their names.
25. Question: Suppose that you wanted to be able to execute a statement like x = x.add( y ), where x and y are Complex objects. What would the return type of the add method have to be?
26. Add methods void multiply( Complex multiplicand ) and void divide( Complex divisor ) that change the real and imaginary components in the way suggested by their names.

Submitting the Project

27. Make any final changes that you want to your project.
28. Generate the HTML documentation for your project.
29. Commit your changes to your CVS module (be sure to include your source file, your report, and your HTML documentation).
30. Tag your CVS module DefiningYourOwnClasses1.

Summary

31. Question: How much time did you spend on Part 1 of DefiningYourOwnClasses? Compare your answer to how much time you had estimated that you would spend. You receive full credit no matter how far off your estimate is!