3: Do you want a car wash with that?
4 (pages 177 - 232) in Java Programming: From Problem Analysis to Program
Design, 3rd Edition, by D. S. Malik, Thomson Course Technology, 2008.
If you wish to read ahead for next week's class you should read Chapter 5
(pages 237 - 311).
Data Type: There
are times in this assignment where you may wish to use the data type ‘char’. It is possible to do the assignment without
it, but easier if you make use of it. We
have not discussed this data type in class. That was intentional. I would like YOU to try and work it out by
reading up on it in your textbook or from an online resource.
Identifiers: Be sure to choose identifiers such as
variable names wisely! Don’t be afraid to have identifiers with two or even
three words in them (although shorter tends to be better). The important thing is that your code should
be easy to follow.
Hard-Coding Values: Earlier on in your testing,
you may get tired of having to type in the “user” choices (e.g. pay by cash,
entering credit card number, type of gas, etc).
Initially, you may want to hard code those values. For example:
// System.out.println("What type of gas, etc,
// gasType = console.nextInt() --> commented out so that I can
// Later, I will uncomment this line
gasType = 1;
//I have hard coded the choice for gas type. Will remove this line later on
goal of this assignment is to practice your understanding of the following
concepts: algorithmic thinking, problem solving, writing a JEnglish version of
your solution, gathering input from the user, use of conditional statements,
use of the Java API, and the use of the Math class.
assignment has two parts. All parts must be completed for full
credit. This is an individual assignment.
Part 1: Do you want a car wash with
have been hired by the development group at Benzina International, a company
manufacturing the machines you interact with when pumping gas as a self-serve
gas station. The team you work with is in charge of designing and
implementing a Java program that drives the dialog with the user. A
different team will use your program and build the touch screen interface, so
for now all your communication with the user will be text based and on the
terminal/console window. Here are the details of the dialogue your
program needs to handle:
- (5 points)
Display a welcome message: "Good morning. Welcome to
yourCuteCompanyName (where you should choose the cute company name that
will be displayed). Please choose a payment method:
- Cash pay inside
- Credit/Debit card"
- (10 points) The
next step will depend on the user selection. If the user chooses the
second option, tell the user to enter his/her credit card number.
Note that you would normally ask the user to swipe the card, but that part
will be done by the machine once this is implemented. For now we are
just simulating this action by having the user enter the number. If
the user chooses the first option, do nothing. Later, when the
program is fully implemented, the machine will not work until the credit
card is authorized through the station network.
- (5 points) The
next step will deal with the car wash selection. You should ask the
user: "Do you want a car wash?" Make sure you clearly
indicate to the user how to respond. We have not covered String
methods so you might want to still use integers or single characters for
user selection. Alternatively, you can look up the String class in
the API and check how to compare two Strings.
- (10 points) If the
user chooses to purchase a car wash you need to present him/her with a
choice of three possible car washes. Include the car wash price in
your menu. For example (feel free to choose your own names and
- Basic ($6.00)
- Premium ($8.00)
- Salt Buster Special
- (10 points) If
the user wants a car wash, you need to generate a random 4-digit code for
the car wash receipt. If the user wants a car wash, you should do
that at this point. Note: If you want a 4-digit random integer, what
should your boundaries be for the formula involving the Math.random()
- (10 points) At
this point you will display the message: "Remove nozzle, select gas
grade, and start pumping." You need to display three types of
gas and their prices. For example (feel free to choose your own
names and prices):
- Basic ($1.75)
- Premium ($2.05)
- Super ($2.25)
- (5 points) Make
sure you capture the user's selection since you will need it in Step 11 to
calculate the final price for the transaction.
- (5 points)
Normally the machine will know when the user is done pumping gas, so we
will skip that part and imagine that it only takes a second. Since
there will be no way to check how many gallons of gas they put in, you
will simulate this by randomly generating the number of gallons
used. This number should be between 5 and 15.
- (5 points)
Display the following message: "Do you want a receipt?"
Note that you should again tell the user how to answer. See the
comments in Step 3 above.
- (5 points) If a
receipt was not requested, simply display a good-bye message.
- (15 points)
Otherwise display in the console window the following information: the
credit card number that was entered (if applicable), the type of car wash
selected (if applicable), the car wash code (if applicable), and the total
price for the transaction. The total price for the transaction is
the price of the selected car wash (if applicable) plus the price of
gas. The price of gas is the number of gallons generated in Step 8
times the price of the selected grade of gas.
How to proceed
- Make sure that you read
the instructions in their entirety and fully understand the problem.
- Create a folder called
YourLastName_H3 where YourLastName is your last name. This folder
will contain all files you need for this assignment. You will zip it
- (10 points) In a
Word or text file, write up the JEnglish version of your solution.
Make sure you include all the small steps you plan to implement.
Also include your name, homework number, and class information.
- Open BlueJ and create a
new project (Click on Project → New Project). Make sure the
project is located in the YourLastName_H3 folder you just created.
Call the project myH3. This step will create a folder called myH3
inside the folder YourLastName_H3.
- Ignore the README.txt
file that BlueJ automatically puts in for you and click on NewClass.
This will create a new class which you should call GetGas.
- Open the GetGas class
and add a description of the class in the comment section, including your
name, date, homework number, and class information.
- Delete everything after
the comment section and set up the class structure with the main
method. The entire dialogue will be coded in the main method.
Use the third lab as a guide.
Part 2: How was it?
points) In the folder YourLastName_H3 create a short ReadMe Word or text
file (ReadMe.doc or ReadMe.txt) containing the following information:
- Your full name
- Class, section, and
- A couple of paragraphs
describing the main difficulties encountered when completing this
assignment as well as the aspect that was the most fun.
must submit the assignment using the online homework submission system on the
COL site. Create a .zip file with the
necessary documents from each part of the assignment and upload this file to
the COL site. The .zip file should be called yourLastName.zip where
yourLastName is your last name and should contain the following items:
- The Word or text file
JEnglish/pseudocode version of your solution
- The folder myH3
containing your BlueJ project with the code
- The ReadMe file with
your reflection on the assignment
assignment is worth 100 points. The points for each required item are