Prerequisites

You need an installation of IntelliJ version 2016.2 or later. The latest version might not yet be in-sync with the Bazel plugin for IntelliJ. It usually becomes so quite quickly after new IDEA versions get released, though. It should then be possible to use the fairly latest IntelliJ release with an updated Bazel plugin.

In addition, Java 8 must be specified on your path or via JAVA_HOME so that building with Bazel via the Bazel plugin is possible.

Tip
 If the synchronization of the project with the BUILD files using the Bazel plugin fails and IntelliJ reports the error Could not get Bazel roots, this indicates that the Bazel plugin couldn’t find Java 8.

Bazel must be installed as described by Building with Bazel - Installation.

Installation of the Bazel plugin

  1. Go to File → Settings → Plugins.

  2. Click on Browse Repositories.

  3. Search for the plugin IntelliJ with Bazel.

  4. Install it.

  5. Restart IntelliJ.

Tip
 If your project’s Bazel build fails with Cannot run program "bazel": No such file or directory, then you may have to set the binary location in the Bazel plugin settings:

  1. Go to Preferences → Other Settings → Bazel Settings.

  2. Set the Bazel binary location.

Creation of IntelliJ project

  1. Go to File → Import Bazel Project.

  2. For Use existing bazel workspace → Workspace, select the directory containing the Gerrit source code.

  3. Choose Import from workspace and select the .bazelproject file which is located in the top directory of the Gerrit source code.

  4. Adjust the path of the project data directory and the name of the project if desired.

Tip
 The project data directory can be separate from the source code. One advantage of this is that project files don’t need to be excluded from version control.

Unfortunately, the created project seems to have a broken output path. To fix it, please complete the following steps:

  1. Go to File → Project Structure → Project Settings → Modules.

  2. Switch to the tab Paths.

  3. Click on Inherit project compile output path.

  4. Click on Use module compile output path.

Recommended settings

Code style

google-java-format plugin

Install the google-java-format plugin by following these steps:

  1. Go to File → Settings → Plugins.

  2. Click on Browse Repositories.

  3. Search for the plugin google-java-format.

  4. Install it.

  5. Restart IntelliJ.

Every time you start IntelliJ, make sure to use Code → Reformat with google-java-format on an arbitrary line of code. This replaces the default CodeStyleManager with a custom one. Thus, uses of Reformat Code either via Code → Reformat Code, keyboard shortcuts, or the commit dialog will use the custom style defined by the google-java-format plugin.

Code style settings

The google-java-format plugin is the preferred way to format the code. As it only kicks in on demand, it’s also recommended to have code style settings which help to create properly formatted code as-you-go. Those settings can’t completely mimic the format enforced by the google-java-format plugin but try to be as close as possible. So before submitting code, please make sure to run Reformat Code.

  1. Download intellij-java-google-style.xml.

  2. Go to File → Settings → Editor → Code Style.

  3. Click on Manage.

  4. Click on Import.

  5. Choose IntelliJ IDEA Code Style XML.

  6. Select the previously downloaded file intellij-java-google-style.xml.

  7. Make sure that Google Style is chosen as Scheme.

In addition, the EditorConfig settings (which ensure a consistent style between Eclipse, IntelliJ, and other editors) should be applied on top of that. Those settings are in the file .editorconfig of the Gerrit source code. IntelliJ will automatically pick up those settings if the EditorConfig plugin is enabled and configured correctly as can be verified by:

  1. Go to File → Settings → Plugins.

  2. Ensure that the EditorConfig plugin is enabled.

  3. Go to File → Settings → Editor → Code Style.

  4. Ensure that Enable EditorConfig support is checked.

Note
 If IntelliJ notifies you later on that the EditorConfig settings override the code style settings, simply confirm that.

Copyright

Copy the folder $(gerrit_source_code)/tools/intellij/copyright (not just the contents) to $(project_data_directory)/.idea. If it already exists, replace it. Then go to File → Settings → Editor → Copyright → Copyright Profiles, and import Gerrit_Copyright.xml to IntelliJ in case it doesn’t pick the copyright up automatically.

File header

By default, IntelliJ adds a file header containing the name of the author and the current date to new files. To disable that, follow these steps:

  1. Go to File → Settings → Editor → File and Code Templates.

  2. Select the tab Includes.

  3. Select File Header.

  4. Remove the template code in the right editor.

Commit message

To simplify the creation of commit messages which are compliant with the Commit Message format, do the following:

  1. Go to File → Settings → Version Control.

  2. Check Commit message right margin (columns).

  3. Make sure that 72 is specified as value.

  4. Check Wrap when typing reaches right margin.

In addition, you should follow the instructions of this section (if you haven’t done so already):

  • Install the Git hook for the Change-Id line.

  • Set up the HTTP access.

Setting up the HTTP access will allow you to commit changes via IntelliJ without specifying your credentials. The Git hook won’t be noticeable during a commit as it’s executed after the commit dialog of IntelliJ was closed.

Run configurations

Run configurations can be accessed on the toolbar. To edit them or add new ones, choose Edit Configurations on the drop-down list of the run configurations or go to Run → Edit Configurations.

Pre-configured run configurations

In order to be able to use the pre-configured run configurations, the following steps are necessary:

  1. Make sure that the folder runConfigurations exists within $(project_data_directory)/.idea. If it doesn’t exist, create it.

  2. Specify the IntelliJ path variable GERRIT_TESTSITE. (This configuration is shared among all IntelliJ projects.)

    1. Go to Settings → Appearance & Behavior → Path Variables.

    2. Click on the + to add a new path variable.

    3. Specify GERRIT_TESTSITE as name and the path to your local test site as value.

The copied run configurations will be added automatically to the available run configurations of the IntelliJ project.

Gerrit Daemon

Warning
 At the moment running this configuration results in a java.io.FileNotFoundException. To debug a local Gerrit server with IntelliJ, use the instructions of Running the Daemon in combination with Debugging a remote Gerrit server.

Copy $(gerrit_source_code)/tools/intellij/gerrit_daemon.xml to $(project_data_directory)/.idea/runConfigurations/.

This run configuration starts the Gerrit daemon similarly as Running the Daemon.

Note
 The Site Initialization has to be completed before this run configuration works properly.

Unit tests

To create run configurations for unit tests, run or debug them via a right-click on a method, class, file, or package. The created run configuration is a temporary one and can be saved to make it permanent.

Normally, this approach generates JUnit run configurations. When the Bazel plugin manages a project, it intercepts the creation and creates a Bazel test run configuration instead, which can be used just like the standard ones.

Debugging a remote Gerrit server

If a remote Gerrit server is running and has opened a debug port, you can attach IntelliJ via a Remote debug configuration.

  1. Go to Run → Edit Configurations.

  2. Click on the + to add a new configuration.

  3. Choose Remote.

  4. Adjust Configuration → Settings → Host and Port.

  5. Start this configuration in Debug mode.

Part of Gerrit Code Review