cs101-F2018-lab9-starter

Designed for use with GitHub Classroom, this repository contains the starter for Laboratory 9 in Computer Science 101. Since the Travis builds for this repository will initially fail (as evidenced by a red ✗ appearing in the commit logs instead of a green ✔), the programmer is responsible for completing all of the steps needed to satisfy the requirements for the assignment, thus causing a ✔ to instead appear in the commit logs.

Introduction

This assignment requires a programmer to implement and test the methods provided by a complete implementation of the ArrayList data structure. More details about the purpose and implementation of the ArrayList are available in Section 7.2 of the textbook. Please note that this assignment will also require you to read and use Java classes that contain a test suite. Specifically, the programmer is responsible for learning how to run and extend a test suite written in the JUnit testing framework, as explained in Section 1.9. As verified by Checkstyle, the source code for all of the Java classes must adhere to all of the requirements in the Google Java Style Guide.

The programmer is also responsible for writing a reflection, stored in the file writing/reflection.md, that responds to the questions in the assignment sheet and explains the challenges that you faced and the solutions you developed. Please note that this is a Markdown file that must adhere to the standards described in the Markdown Syntax Guide. Remember, you can preview the contents of a comitted Markdown file by clicking on the name of the file in your GitHub repository. Finally, don't forget that your writing/reflection.md file should adhere to the Markdown standards established by the Markdown linting tool and the writing standards set by the Proselint tool.

The source code in the submitted Java source code files must also pass additional tests set by the GatorGrader tool. For instance, GatorGrader will check to ensure that ArrayList has println statements that can produce the output from interacting with this array-based structure. Gradle will also run a JUnit test suite that will perform many checks on your implementation of the Java classes. Critically, the focus of this assignment is to ensure that you can implement an ArrayList that passes the entire test suite. More details about the GatorGrader checks are included later in this document and in the assignment sheet.

When you use the git commit command to transfer your source code to your GitHub repository, Travis CI will initialize a build of your assignment, checking to see if it meets all of the requirements. If both your source code and writing meet all of the established requirements, then you will see a green ✔ in the listing of commits in GitHub. If your submission does not meet the requirements, a red ✗ will appear instead. The instructor will reduce a programmer's grade for this assignment if the red ✗ appears on the last commit in GitHub immediately before the assignment's due date.

A carefully formatted assignment sheet for this project provides more details about the steps that a computer scientist should take to complete this assignment. You can view this assignment sheet by visiting the listing of laboratories on the course web site.

Learning

If you have not done so already, please read all of the relevant GitHub Guides that explain how to use many of the features that GitHub provides. In particular, please make sure that you have read the following GitHub guides: Mastering Markdown, Hello World, and Documenting Your Projects on GitHub. Each of these guides will help you to understand how to use both GitHub and GitHub Classroom.

To do well on this assignment, you should also read Section 1.5.2 to learn more about iteration constructs and Section 1.9 to learn more about testing. Please read all of the content and study all of the technical diagrams and source code segments in Sections 7.1 and 7.2. Finally, please see the course instructor or one of the teaching assistants or tutors if you have questions about any of these reading assignments.

Commands

To get started in using the GatorGrader tool, you can change into the directory for this assignment and type the command gradle grade in your terminal. Running this command will produce a lot of output that you should carefully inspect. If the output indicates that GatorGrader judges that there are no mistakes in the assignment, then this means that your source code and writing are passing all of the automated baseline checks. However, if the output indicates that there are mistakes, then you will need to understand what they are and then try to fix them.

Running this command will produce a lot of output that you should carefully inspect. If the last line of the output indicates that GatorGrader judges that there are no mistakes in the assignment, then this means that your source code and writing are passing all of the automated checks. However, if the last line of the output indicates that there are mistakes, then you will need to understand what they are and then try to fix them.

You can also complete several important Java programming tasks by using the gradle tool. For instance, you can compile (i.e., create bytecode from the program's source code if it is a correct program) the program using the command gradle build. There are also additional commands that you can type:

• gradle clean: clean the project of all the derived files
• gradle check: check the quality of the code using Checkstyle
• gradle build: create the bytecode from the Java source code
• gradle run: run the Java program in the command-line
• gradle cleanTest: clean the JUnit test suite of derived files
• gradle test: run the JUnit test suite and produce report
• gradle tasks: display details about the Gradle system

To run one of these commands, you must be in the home directory for this assignment where the build.gradle file is located. Then, you can type the command in the terminal and study the output.

Output

Typing the command gradle run in the terminal window produces the following output for the instructor's version of labnine.list.ArrayList. Notice that this program will create an ArrayList of size ten and then first the first and then the last element. It is critical that your program does not crash by throwing an exception when performing these operations on an instance of an ArrayList. Finally, please note that this laboratory assignment invites you to run comprehensive JUnit test suites for two Java classes. While these test suites do not produce any output, you should carefully inspect their tests so that you understand their strategy. In particular, it is critically important that you study and understand every test case in TestArrayList!

ArrayList before removing first element:
(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)

ArrayList after removing first element:
(8, 7, 6, 5, 4, 3, 2, 1, 0)

ArrayList after removing last element:
(8, 7, 6, 5, 4, 3, 2, 1)

Checking

In addition to making the checks that are mentioned in the introduction to this document, your final submission must meet the following requirements.

• labnine/ArrayList.java:

  • Contains at least twenty-five multi-line comments in the JavaDoc standard
  • Contains exactly two StringBuilder uses in the toString method
  • Contains exactly zero println statements to produce program output
  • Contains exactly zero of the comment fragment that marks incomplete tasks
  • Runs without crashing and produces the correct output in the terminal window

• writing/reflection.md:

  • Passes the checks performed by the Markdown linting tool
  • Passes the checks performed by the Prose linting tool
  • Contains exactly eight contiguous paragraphs of formatted text
  • Each of the contiguous paragraphs contains at least 50 words

• GitHub repository:

  • Contains Java source code that passes all of the provided JUnit tests
  • Contains five commits beyond the repository's starting number of commits

Updates

If the course instructor updates the provided material for this assignment and you would like to receive these updates, then you can type this command in the main directory for this assignment:

git remote add download git@github.com:Allegheny-Computer-Science-101-F2018/cs101-F2018-lab9-starter.git

You should only need to type this command once; typing the command additional times may yield an error message but will not negatively influence the state of your repository. Now, you are ready to download the updates provided by the course instructor by typing:

git pull download master

This second command can be run whenever the course instructor needs to provide you with new source code for this assignment. However, please note that, if you have edited the files that the course instructor updated, running the previous command may lead to Git merge conflicts. If this happens, you may need to manually resolve them with the help of the instructor or a teaching assistant.

Travis

This assignment uses Travis CI to automatically run the checking programs every time you commit to your GitHub repository. The checking will start as soon as you have accepted the assignment, thus creating your own private repository, and the course instructor enables Travis for it. If you are using Travis for the first time, you will need to authorize Travis CI to access the private repositories that you created on GitHub.

Requirements

The GatorGrader software that supports the checking of this assignment was developed for the following software and versions:

• Gradle 4.6
• Java 1.8.0
• JUnit 4.9.0
• MDL 0.4.0
• Proselint 0.8.0
• Python 3.6

Problems

If you have found a problem with this assignment's provided source code, then you can go to the Computer Science 101 Lab 9 Starter repository and create an issue by clicking the "Issues" tab and then clicking the green "New Issue" button. If you have found a problem with the GatorGrader tool and the way that it checks you assignment, then you can follow the aforementioned steps to create an issue in its repository. To ensure that your issue is properly resolved, please provide as many details as is possible about the problem that you experienced. If you discover a problem with the laboratory assignment sheet, then please raise an issue in the cs101-F2018-sheets repository and mention this assignment.

Students who find, and use the appropriate GitHub issue tracker to correctly document, a mistake in any aspect of this laboratory assignment will receive free laptop stickers and extra credit towards their grade for it.

Assistance

If you are having trouble completing any part of this project, then please talk with either the course instructor or a teaching assistant during the laboratory session. Alternatively, you may ask questions in the Slack team for this course. Finally, you can schedule a meeting during the course instructor's office hours.