Intellij is an IDE specifically built for writing Java software. Because it is a first class Java editor, it offers much better support than the versions of VS Code that WPI provides us, including but not limited to:
- Better and more reliable intellisense
- Better refactoring/renaming support (especially at the class level)
- A much better Git integration tool
- Smarter Command and Subsystem class creation
- Better Checkstyle and PMD integration (if you choose to adopt a styleguide)
- Allows support of multi "module" projects (aka subprojects, like reusable libraries, a separate project for a dashboard, etc))
The easiest way to install and update Intellij is by download Jet Brains Toolbox application. This will alert you whenever there is a new version, and allows you to easily download their other IDEs if you ever want to dabble in Python or Web Development
Once Toolbox has been installed, open it and select the "Intellij Community Edition", and run the installer
Note
The FRC Intellij Plugin revolves around the FRC competition season and often will lag behind, and end up incompatible with the newer versions of the intellij IDE. Because of this, it is recommended that you install the latest supported version listed on the plugins webpage.
It is also recommended that everyone on the team use the same version, and that you lock that version down at the start of the build season.
The latest supported version is 2021.3.3
To get the best experience out of Intellij, we need to install some additional plugins.
To install a plugin, go to File -> Settings -> Plugins. Select the "Marketplace" for the following plugins, and install them. Once they are all done, you will need to restart Intellij
- FRC
- Checkstyle-IDEA
Intellij comes bundled with its own version of java, but to be more consistent with how VS code operates, it is highly recommended (and in some cases required) to point intellij to the offically supported version of the JDK distributed with the VS Code Tools installer.
To add the wpilib JDK, navigate to File -> Project Structure -> Project -> SDK -> Edit. Click the "+" button to add a new SDK, and navigate to the folder where the WPI tools where installed. On windows, this will be something like C:\Users\Public\wpilib\2022\jdk
When you open intellij, you will see a screen that looks like this.
The options in this dropdown allow you to do all of the important things we could do in VS code like deploying code to the robot, opening the RioLog, as well as allowing you to run the simulator.
Note
Unlike VS code, you have to select what you want to run AND THEN press the green play button, they don't auto run when selected like in VS Code.
The version control tab allows you to see your current changes, easily look at diffs at a quick glance, and kick off the commit/push process. There are a lot more options available in the "VCS -> Git" toolbar on the top.
This is where we can see all of the files for our project. Unlike VS Code, you have to manually open folders that have only one sub-folder in them which can be a little bit more tedious. Our robot code is located under the "src/main/java/frc.robot" folders
Note
You can have intellij display the Java packages "Flattened", i.e. com.scra.codelabs or "Not Flattened", like a typical OS directory structure, whichever you prefer.
When you are connected and communicating with the robot, the RioLog will be displayed here
The Intellij FRC plugin is an open source project to provide a lot of helpful features for us when we are developing software for FRC robots. It eases the creation of Subsystems and Commands by filling in a lot of the boiler plate code for use.
Right click on the package where you want to put the subsystem (almost certainly frc.robot.subsystems), and click "New -> FRC -> Subsystem"
The subsystem it creates is very sparse. At the very least, you will probably want to add a periodic function
Right click on the package where you want to put the command, and click "New -> FRC -> Command". You will be given the option to select what subsystems this command requires to save you some typing.
