Introduction to Computer Science II by James Tam

CPSC 233: Assignment 2 (Worth 2%)

Due Friday October 1

New concepts to be applied for the assignment

Writing programs that consist of more than one class (a very simple object-oriented program).

Writing a lucky number generator

The requirements for this assignment are identical to the ones for Assignment 1, except that you must now employ two classes: 1) A "Driver" class (that contains the main method) 2) Another class, "Lucky", that implements the operations described in the previous assignment. In assignment one it was likely that your main method contained all of your program code. For the second assignment it is likely that your main method will now just instantiate an instance of class Lucky and perhaps include a few method calls:

One approach to the second assignment:
class Driver
{
          public static void main (String [] args)
         {
                  int ageModifier;
                  int petModifier;
                  Lucky generator = new Lucky ();
                      :        :                :        :

                  generator.introduction();
                  ageModifier = generator.determineAgeModifier ();
                  petModifier = generator.determinePetModifier();
                      etc.
                  // The loop that asks the user if they want to re-run the program will be in the main method and it will encompass
                  // all the calls to the methods of class Lucky.
          }
   }

Another (better) approach to the second assignment:
class Driver
{
        public static void main (String [] args)
        {
                Lucky generator = new Lucky ();
                generator.start();
        }
}

With this second approach the main loop for the program and the calls to the different methods of class Lucky are contained in the "start" method of class Lucky.

class Lucky
{
        public void start ()
        {
                int ageModifier;
                int petModifier;

                introduction();
                ageModifier = determineAgeModifier ();
                petModifier = determinePetModifier();
                    etc.
                // The loop that asks the user if they want to re-run the program will be in method start and it will encompass all
                // the calls to the methods of class Lucky.
        }

        public int determineAgeModifier ()
       {
                :            :

            return ageModifier;
        }

            :    :        :        :

}

You cannot implement a solution to Assignment 2 that employs only a single class nor can you implement a solution that uses static methods - aside from the main method and the methods contained in the tio library and the ones in class "Character". (If you don't know what I mean by implementing a program using only static method calls then that's a good thing - it's bad style in terms of the Object-Oriented approach).

To help you get started here is an outline of the methods that you may wish to implement in class Lucky:

public void introduction (): Most programs provide some sort of description of the program (or more likely a splash screen) as the program loads. The description may briefly indicate to the user what the program does or the splash screen may at least indicate to the user that the program is being loaded.
public int determineAgeModifier (): This method prompts the user to enter his or her age. This value is stored in an integer and returned back to the caller of this method.
public int determinePetModifier (): This method prompts the user to enter in the type of pet that they own. Based on the value entered, the program will then determine the numeric value for the pet modifier and return this value back to the caller of the method.
public int determineInitialModifier (): This method prompts the user to enter his or her initial for their last name. Based on the value entered, the program will then determine the numeric value for the initial modifier and return this value back to the caller of the method.
public int determineEducationModifier (): This method prompts the user to enter his or her current level of education (if the person is currently a student) or the highest level of education that he or she completed (if the person is no longer a student). Based on the value entered, the program will then determine the numeric value for the education modifier and return this value back to the caller of the method.

Note: Your implementation may of course differ but just make sure that each method performs a well-defined task and that the amount of code in each method is fairly balanced (e.g., don't just write one method that does all of the above operations).

Grading

Like Assignment 1, there will be three possible grade levels with this assignment. However, all submissions must implemented using two classes: a driver class which is the starting point for the program and class Lucky which implements all the requirements specified for Assignment 1.

Other submission requirements

All the requirements listed in Assignment 1 also apply for this assignment except that you must now submit and print out two source code files (one for the driver class and one for class Lucky).

1. Good coding style and documentation: They will play a role in determining your final grade for this assignment. Your grade can be reduced by a letter step or more (e.g., 'A' to 'A-' for poor programming style such as employing poor naming conventions for identifiers, insufficient documentation or the use of global variables).

2. Include a README file in your submission: For this assignment your README file must indicate what grade level has been completed (A, B or C). This will allow your marker to quickly determine what he or she must look for and speed up the marking process.

3. Assignments (source code and the README file) must be electronically submitted via submit. In addition a paper print out of the source code must be handed into the assignment drop box for the lab that you are registered in (located on the second floor of the Math Sciences building). Electronically submitting the assignment allows your marker to run the code in order to quickly determine what features were implemented. Providing a paper printout makes it easier for your marker to read and flip through your source code.