Mix Tape Calculator
CSc 103 Programming Project
The goal of this project is to write a Java program for the console
version of the Mix Tape Calculator
application.
Objectives
The objectives of this assignment are
- to convert a procedural application into an Object Oriented
solution.
- to learn to use ADT's effectively to build simple, flexible,
maintainable, reusable software components.
- to build an application that uses the List interface from the
Collections framework.
- to use unit testing effectively in constructing a moderately
complex application.
Overview
In CSc 101 students implemented a procedural solution using the C
language to the PlayList Calculator problem. The problem
specification has been enhanced to include a Swing GUI. Your job is to
convert the C implementation into Java and take advantage of Object
Oriented principles to create a better quality design that contains the
features required by the enhanced
specification.
Software Design
The instructor has written the code for the Graphical "front end" part
of the application.
You are provided a JAR file containing the MixTapeGUI
class and other components of the GUI. Your assignment is to
write the "back end" components and a console user interface.
Here are the Javadoc for the instructor supplied components:
MixTapeApp
Natural
MixTapeCalc.jar
contains the
.class files for the instructor components
in a
JAR formatted file. Don't unzip this file,
add it as a
custom library
to your BlueJ or NetBeans project.
MixTapeCalc.jar (Updated 2014.1.22)
You must implement these modules:
Here is the C implementation of the
original problem.
playlistCalculator.c
Testing
Your components will be tested with instructor reference
tests. The reference tests are JUnit tests of your classes.
MixTapeGUI is not used in testing.
MilesDavis.m3u
Sample Execution
Here is the
output
produced by running MixTapeConsole with
this
user input
.
You can also run the instructor's solution at
Oracle of Java
Handing in Your Source
Electronically
- Submit a zip file containing your source code, unit tests, and data
files to Web-CAT. You do not need to submit MixTapeCalc.jar.
- When Web-CAT assigns a 100% score to your work, you should
finalize
your Time Log and submit it to the instructor at the next class
meeting.
GRADING
The problem coverage is worth 70% of your score.
In order to obtain 90% you
also need to obtain 20/20 on the "Style/Coding" portion of the score.
The last 10% of the score results from manually grading your solution
to see that you followed the
algorithm
design guidelines.
On this project your solution must conform to the class coding
standard. Your unit tests
must demonstrate "statement" coverage (they cause every
statement in your program to be executed.) There is a limit of 20
submissions.
Lessons Learned
Previous students made these comments after completing this assignment:
-
Write thorough JUnit tests.
Finding defects in individual units is easier than
in the integrated system.
-
Write tests before coding.
Get immediate feedback.
More focused.
Makes very concrete what each method should do.
-
Study the provided code and javadocs.
Don't go your own way and then realize yours won't interface.
-
Don't procrastinate.
FAQ
Q:
Can you give me a hint on what the constructor for MixTapeConsole does?
A:
The constructor allows easy JUnit testing.
Here's a
tutorial video
explaining the concept,
and here's the
code for the example project.
Q: What would you like us to do for a Quit command in the MixTapeConsole
class. System.exit(0); seems to crash web cat.
A: Simply allow execution to finish the display() method normally.
(Also, close the Writer).
Q: How can I force my test to throw IOException?
A: See the
JUnit FAQ
Q: Should MixTapeModel do anything on it's own or does it delegate everything
to SongPool and PlayList.
A: Everything is delegated except addToMix. All the other methods have
exactly ONE line of code,
which is a call to the appropriate method in SongPool or PlayList.
The pseudocode for addToMix() is
// IF there is room in the playlist for another song THEN
// Move selected song to play list.
// RETURN true;
// END IF
// RETURN false;
Q: Can I run the instructor GUI with my classes?
A: Yes. Open a terminal window and from your project directory issue this command:
In BlueJ:
java -cp +libs/MixTapeCalc.jar:. MixTapeGUI
In NetBeans:
java -cp lib/MixTapeCalc.jar:build/classes MixTapeGUI
Q: I don't understand why Web-CAT is reporting this compile error,
it isn't even my code:
error: unreported exception IOException; must be caught or declared to be thrown
model.loadM3U(new java.io.File("MilesDavis.m3u"));
A: Your loadM3U() method must NOT throw IOException.
You have to catch it yourself.
Q: Where should I catch IOException when writing the file?
A: Since the spec doesn't require the application to inform the user
about file i/o errors we can catch any IOExceptions in the same method
that does the file writing and simply print a stack trace to standard out.
Q: Can I add a compareTo() method to TimeDuration?
A: No. The solution can be achieved with the existing methods. If you
can't figure it out, ask the instructor for a hint.
Q: Why would my unit tests pass on my computer but fail on Web-CAT?
A: Does your computer run Windows? Heed
this advice.
Q: Is there an easy way to make a zip file in NetBeans for submitting
to Web-CAT?
A: Yes, add this
code snippet to your build.xml file to create a "zip" target.
Q: What problems did students in previous problems have with this assignment?
A: Four categories: Tools, Specs, Testing, Time Management
Q: Do you have any examples of "algorithm" mistakes to be avoided?
A:
Don't make an instance of Vector in Playlist or SongPool.
Don't put a return inside an if statement
Don't add extra public methods
Use Scanner, not BufferedReader
And for heaven's sake, don't use recursion.
Document History
4/18/2017 Added java command for NetBeans to FAQ.
4/11/2017 Add link to Ant zip target
4/10/2017 Add items to FAQ
3/30/2017 updated for CSc 305
1/26/2014 updated FAQ
10/10/2012 Added sample console output
9/24/2009 Available for Fall 2009