BYU C S 240 Code Style/Quality Checker

This repository holds the source code for the "Code Quality Checker" for the BYU C S 240 class that is not part of the base checkstyle repository

The code is based on checkstyle and includes the checkstyle built-in checks. Checkstyle also allows for writing your own custom checks; most of the code in this repository is either a custom check or part of a test for a custom check.

Checkstyle is based on the Visitor Pattern, often representing Java code in an Abstract Syntax Tree (AST). Because of this, any code must compile in order to be used as input for the checker. (Note to future TA's: if C S 236 still had you building a Datalog parser, an AST is somewhat similar to the list of tokens except it's a tree instead of a list of tokens)

Building

This repository uses Maven for dependencies and building so you can build it with mvn package after which a jar will be in the target directory as checkstyle-<version>.jar, like checkstyle-1.0.8.jar.

Running

java -jar path/to/jar/checkstyle-<version>.jar -c <check file name>.xml <path to files/folders to check (can be multiple)

C S 240 Chess project running example (cs240_checks.xml is in the jar and usable from the jar, but you can substitute it if needed):

java -jar ./checkstyle-1.0.8.jar -c cs240_checks.xml ./client/ ./server/ ./shared/

Code Tour

└─ src
   ├─ main
   │  ├─ java/edu.byu.cs240.checkstyle                      Root folder for custom checkstyle checks
   │  │  ├─ util                                            Contains utility functionality used in multiple places          
   │  │  └─ <package name>                                  Contains custom checks for a particular quality rubric category
   │  │      └─ <check name>.java                           Contains code necessary for checking <check name>
   │  └─ resources
   │     ├─ checkstyle_packages.xml                         Informs Checkstyle where to find custom check classes
   │     └─ cs240_checks.xml                                Informs Checkstyle which checks to run. Used as an argument when running checkstyle. Named similarly 
   │                                                            to google_checks.xml and sun_checks.xml, which also appear in the jar.
   └─ test
      │  ├─ java/edu.byu.cs240.checkstyle                   Root folder for tests for the custom checkstyle checks
      │  ├─ CheckTest.java                                  Base abstract class for writing tests for custom checks          
      │  └─ <package name>                                  Contains tests for custom checks for a particular quality rubric category. Most extend CheckTest
      │      └─ <check name>Test.java                       Tests for <check name>.java inside main. Uses input files from test/resources
      └─ resources
         └─ edu.byu.cs240.checkstyle                        Root folder for code input files used to test the checks. Generally nonsense code
             │                                                  with specific problems we expect the check to find. Many contain no errors (for
             │                                                  the specified check) to make sure it doesn't flag in unexpected cases it shouldn't
             └─ <package name>.testInputs.<check name>      Test input files for a specific check