cs100f2019-practical5-starter

Designed for use with GitHub Classroom, this repository contains the starter materials for Practical 5 in Computer Science 100.

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 a Java program, called DiceRoll, that will produce textual output that rolls dice and performs simple mathematical operations on their output. Please see the laboratory assignment sheet for more details. As verified by Checkstyle, the source code for the DiceRoll.java file must adhere to all of the requirements in the Google Java Style Guide.

The source code in the DiceRoll.java file must also pass additional tests set by the GatorGrader tool. Specifically, GatorGrader will check the following characteristics of your implementation:

• The DiceRoll program must:
  • Contain at least seven single-line comments and two multi-line comments
  • Declare and use at least two variables of type int
  • Use appropriate methods of the Math class to perform mathematical operations
  • Call println six times to produce the desired output

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 your source code meets 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.

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 practicals on the course web site.

Continuous 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.

Students who want to learn more about how to use Docker should review the Docker Documentation. Students are also encouraged to review the documentation for their text editor, which is available for text editors like Atom and VS Code. You should also review the Git documentation to learn more about how to use the Git command-line client. In addition to talking with the instructor and technical leader for your course, students are encouraged to search StackOverflow for answers to their technical questions.

System Commands

This project invites students to enter system commands into a terminal window. This assignment uses Docker to deliver programs, such as gradle and the source code and packages needed to run GatorGrader, to a students' computer, thereby eliminating the need for a programmer to install them on their development workstation. Individuals who do not want or can not install Docker can optionally install of the programs mentioned in the Project Requirements section of this document. Once all the required programs are installed locally on a machine, a software developer can type the various gradle commands directly in the terminal.

Using Docker

Once you have installed Docker Desktop, you can use the following docker run command to start gradle grade as a containerized application, using the DockaGator Docker image available on DockerHub.

docker run --rm --name dockagator \
  -v "$(pwd)":/project \
  -v "$HOME/.dockagator":/root/.local/share \
  gatoreducator/dockagator

The aforementioned command will use "$(pwd)" (i.e., the current directory) as the project directory and "$HOME/.dockagator" as the cached GatorGrader directory. Please note that both of these directories must exist, although only the project directory must contain something. Generally, the project directory should contain the source code and technical writing of this assignment, as provided to a student through GitHub. Additionally, the cache directory should not contain anything other than directories and programs created by DockaGator, thus ensuring that they are not otherwise overwritten during the completion of the assignment. To ensure that the previous command will work correctly, you should create the cache directory by running the command mkdir $HOME/.dockagator. If the above docker run command does not work correctly on the Windows operating system, you may need to instead run the following command to work around limitations in the terminal window:

docker run --rm --name dockagator \
  -v "$(pwd):/project" \
  -v "$HOME/.dockagator:/root/.local/share" \
  gatoreducator/dockagator

Since the above docker run command uses a Docker images that, by default, runs gradle grade and then exits the Docker container, you may want to instead run the following command so that you enter an "interactive terminal" that will allow you to repeatedly run commands within the Docker container.

docker run -it --rm --name dockagator \
  -v "$(pwd)":/project \
  -v "$HOME/.dockagator":/root/.local/share \
  gatoreducator/dockagator /bin/bash

Once you have typed this command, you can use the GatorGrader tool in the Docker container by typing the command gradle grade in your terminal. Running this command will produce a lot of output that you should carefully inspect. If GatorGrader's output shows that there are no mistakes in the assignment, then 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.

Here are some additional commands that you may need to run when using Docker:

• docker info: display information about how Docker runs on your workstation
• docker images: show the Docker images installed on your workstation
• docker container list: list the active images running on your workstation
• docker system prune: remove many types of "dangling" components from your workstation
• docker image prune: remove all "dangling" docker images from your workstation
• docker container prune: remove all stopped docker containers from your workstation
• docker rmi $(docker images -q) --force: remove all docker images from your workstation

Using Gradle

You can 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 correct) the program using the command gradle build. Here are some other commands that you can type:

• gradle grade: run the GatorGrader tool to check your work
• 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 tasks: display details about the Gradle system

To run one of these commands, you must be in the main (i.e., "home base") directory for this assignment where the build.gradle file is located.

Using Travis CI

This assignment uses Travis CI to automatically run GatorGrader and additional 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 and/or GitHub 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. If you do not see either a yellow ● or a green ✔ or a red ✗ in your listing of commits, then please ask the instructor to see whether or not Travis CI was correctly enabled.

System Requirements

We developed this assignment to work with the following software and versions:

• Docker Desktop
• Operating Systems
  • Linux
  • MacOS
  • Windows 10 Pro
  • Windows 10 Enterprise
• Programming Language Tools
  • Gradle 5.4
  • OpenJDK 11.0.4
  • Python 3.6 or 3.7

Reporting Problems

If you have found a problem with this assignment's provided source code or documentation, then you can go to the Java Assignment Starter 100-01 repository and raise an issue. If you have found a problem with the GatorGrader tool and the way that it checks your assignment, then you can also raise an issue in that 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 assignment sheet for this project, then please raise an issue in the GitHub repository that provides the assignment sheets for your course.

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

Receiving Assistance

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