Migrate¶

From palantir-java-format¶

open-java-format 2.98.0.3 formats with the code of palantir-java-format 2.98.0, under new names and built in the open. The output is the same except for two fixes. A long string is no longer split after an escaped backslash followed by n, as if that were a line break. Imports with comments between them are formatted rather than rejected. Anywhere else, switching produces no formatting diff and needs no reformatting commit.

Checked on 341 source files, about 24,000 lines: palantir-java-format 2.98.0 and open-java-format 2.98.0.2 give byte-identical output. On the JDK 21 sources, 2.98.0.3 reformats 5 of the files that 2.98.0.2 leaves unchanged when run again, all because of the first fix.

The Java packages are unchanged as well. Only the names in your build and your scripts change.

The fourth number of the version counts builds of an upstream version: 2.98.0.1 was the first build of 2.98.0, and 2.98.0.2 is the second.

Gradle¶

 plugins {
-    id 'com.palantir.java-format' version '2.98.0'
+    id 'dev.openjavaformat.java-format' version '2.98.0.3'
 }

-palantir.native.formatter=true
+openjavaformat.native.formatter=true

The plugin needs Gradle 9 and Java 21 or later. Gradle plugin covers the settings and multi-project builds.

Command line and scripts¶

Remove --palantir: there is one style, so no flag chooses it. Take the binary or the jar from our releases.

Libraries that call the formatter¶

Change the coordinates. The imports stay as they are, because the packages did not move.

-implementation 'com.palantir.javaformat:palantir-java-format:2.98.0'
+implementation 'dev.openjavaformat:open-java-format:2.98.0.3'

In a pom.xml it is the same change of groupId, artifactId and version.

Spotless¶

With Gradle, remove palantirJavaFormat() from the spotless block and apply our plugin, which adds its own step. Maven has no way yet. Spotless has both.

IntelliJ IDEA¶

1. Disable or uninstall the palantir-java-format plugin. Both plugins take over Reformat Code for Java, so only one of them should be enabled.
2. Install open-java-format from the JetBrains Marketplace.
3. Enable it for the project again. The setting now lives in .idea/open-java-format.xml, and the old .idea/palantir-java-format.xml is ignored and can be deleted. A project that applies the Gradle plugin gets the new file written when it is imported.

Eclipse¶

Remove palantir-java-format-eclipse-plugin-*.jar from the dropins folder and follow Eclipse for the new jar. The --add-exports lines in eclipse.ini stay.

From google-java-format¶

The style is different, so this migration comes with one reformatting commit. Lines go from 100 to 120 columns, indentation from 2 to 4 spaces, a lambda stays on the line where it starts, and a long call chain breaks into one call per line. The home page shows the same method in both styles.

1. Set the formatter up: Get started. The --add-exports JVM flags you may already have for google-java-format are the same.

2. Format everything once and commit only that:

   open-java-format --replace $(git ls-files '*.java')
   git commit -am "Reformat with open-java-format"
   

3. Keep git blame useful by listing that commit in .git-blame-ignore-revs:

   git rev-parse HEAD >> .git-blame-ignore-revs
   git add .git-blame-ignore-revs
   git commit -m "Ignore the reformatting commit in blame"
   git config blame.ignoreRevsFile .git-blame-ignore-revs
   

   GitHub reads that file on its own. The git config line is for local clones, and each developer runs it once.

4. In IntelliJ IDEA disable the google-java-format plugin before enabling open-java-format.