TruEra

TruEra specific changes are in the truera branch.

Merge latest changes from upstream

Fetch all tags (which will be releases) from upstream and push it to TruEra fork.

git fetch upstream --tags
git push origin --tags

Update the truera branch with master.

git checkout master
git merge upstream/master
git push origin HEAD
git checkout truera
git rebase -i origin/master

We will keep the changes to minimum and hoping that there won't be any merge conflicts.

Generating a new build from a new release

Official source for each release is maintained as a git tag. When generating a new TruEra version using a particular release start by checking out the tag as a branch. For instance, for v1.15.0 you will need:

git checkout -b release/v1.15.0 v1.15.0

Then cherry-pick the TruEra specific changes onto this branch. Currently there is only one change that needs to be cherry-picked.

git cherry-pick 0f8d45adec4032552bbc0f9c6a26815863b8b273
git push --set-upstream origin release/v1.15.0

Build the source code: NOTE: Since we are increasing the line length, a lot of tests will fail legitimately, please ignore those.

mvn clean install -DskipTests

The Jar will be generated in core/target/google-java-format-<verssion>-all-deps.jar.

google-java-format

google-java-format is a program that reformats Java source code to comply with Google Java Style.

Using the formatter

from the command-line

Download the formatter and run it with:

java -jar /path/to/google-java-format-${GJF_VERSION?}-all-deps.jar <options> [files...]

The formatter can act on whole files, on limited lines (--lines), on specific offsets (--offset), passing through to standard-out (default) or altered in-place (--replace).

To reformat changed lines in a specific patch, use google-java-format-diff.py.

Note: There is no configurability as to the formatter's algorithm for formatting. This is a deliberate design decision to unify our code formatting on a single format.

IntelliJ, Android Studio, and other JetBrains IDEs

A google-java-format IntelliJ plugin is available from the plugin repository. To install it, go to your IDE's settings and select the Plugins category. Click the Marketplace tab, search for the google-java-format plugin, and click the Install button.

The plugin will be disabled by default. To enable it in the current project, go to File→Settings...→google-java-format Settings (or IntelliJ IDEA→Preferences...→Other Settings→google-java-format Settings on macOS) and check the Enable google-java-format checkbox. (A notification will be presented when you first open a project offering to do this for you.)

To enable it by default in new projects, use File→Other Settings→Default Settings....

When enabled, it will replace the normal Reformat Code action, which can be triggered from the Code menu or with the Ctrl-Alt-L (by default) keyboard shortcut.

The import ordering is not handled by this plugin, unfortunately. To fix the import order, download the IntelliJ Java Google Style file and import it into File→Settings→Editor→Code Style.

Eclipse

The latest version of the google-java-format Eclipse plugin can be downloaded from the releases page. Drop it into the Eclipse drop-ins folder to activate the plugin.

The plugin adds a google-java-format formatter implementation that can be configured in Window > Preferences > Java > Code Style > Formatter > Formatter Implementation.

Third-party integrations

• Gradle plugins
  • spotless
  • sherter/google-java-format-gradle-plugin
• Apache Maven plugins
  • spotless
  • spotify/fmt-maven-plugin
  • talios/googleformatter-maven-plugin
  • Cosium/maven-git-code-format: A maven plugin that automatically deploys google-java-format as a pre-commit git hook.
• SBT plugins
  • sbt/sbt-java-formatter
• maltzj/google-style-precommit-hook: A pre-commit (pre-commit.com) hook that will automatically run GJF whenever you commit code to your repository
• Github Actions
  • googlejavaformat-action: Automatically format your Java files when you push on github

as a library

The formatter can be used in software which generates java to output more legible java code. Just include the library in your maven/gradle/etc. configuration.

google-java-format uses internal javac APIs for parsing Java source. The following JVM flags are required when running on JDK 16 and newer, due to JEP 396: Strongly Encapsulate JDK Internals by Default:

--add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED
--add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED
--add-exports jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED
--add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED
--add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED

Maven

<dependency>
  <groupId>com.google.googlejavaformat</groupId>
  <artifactId>google-java-format</artifactId>
  <version>${google-java-format.version}</version>
</dependency>

Gradle

dependencies {
  implementation 'com.google.googlejavaformat:google-java-format:$googleJavaFormatVersion'
}

You can then use the formatter through the formatSource methods. E.g.

String formattedSource = new Formatter().formatSource(sourceString);

or

CharSource source = ...
CharSink output = ...
new Formatter().formatSource(source, output);

Your starting point should be the instance methods of com.google.googlejavaformat.java.Formatter.

Building from source

mvn install

Contributing

Please see the contributors guide for details.

License

Copyright 2015 Google Inc.

Licensed under the Apache License, Version 2.0 (the "License"); you may not
use this file except in compliance with the License. You may obtain a copy of
the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
License for the specific language governing permissions and limitations under
the License.