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-1.5-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

A google-java-format IntelliJ plugin is available from the plugin repository.

The plugin will not be enabled by default. To enable it in the current project, go to "File→Settings...→google-java-format Settings" and check the "Enable" checkbox.

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.

Eclipse

A 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.

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.

Maven

<dependency>
  <groupId>com.google.googlejavaformat</groupId>
  <artifactId>google-java-format</artifactId>
  <version>1.5</version>
</dependency>

Gradle

dependencies {
  compile 'com.google.googlejavaformat:google-java-format:1.5'
}

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.