SCM Integration

The plugin supports integrating with source control management (SCM) systems to automatically derive per-file properties such as the year of the last change or the original author. These properties can then be used as placeholders in your license header templates.

How It Works

SCM integration is implemented as PropertiesProvider extensions. Each integration module is an optional dependency that you add to the plugin. Once on the classpath, it automatically provides additional properties for each file being processed.

Available Integrations

Module	Source	Key Properties
Git	Git commit history	license.git.copyrightLastYear, license.git.copyrightYears, author info
Subversion	SVN metadata	license.svn.lastchange.year, license.svn.years.range
Filesystem	File modification time	license.fs.copyrightLastYear, license.fs.copyrightYears

Adding an Integration

Add the desired integration module as a <dependency> of the plugin (not the project):

<plugin>
  <groupId>com.mycila</groupId>
  <artifactId>license-maven-plugin</artifactId>
  <version>5.0.0</version>
  <dependencies>
    <dependency>
      <groupId>com.mycila</groupId>
      <artifactId>license-maven-plugin-git</artifactId>
      <version>5.0.0</version>
    </dependency>
  </dependencies>
</plugin>

Handling Shallow Clones

When using Git or SVN integration, accurate property values (especially copyright years) require access to the full commit history. Shallow clones (common in CI environments with git clone --depth=1) may produce incorrect results.

The plugin provides three configuration options to handle this:

Option	Property	Default	Behaviour
warnIfShallow	license.warnIfShallow	true	Log a warning when a shallow clone is detected
skipOnShallow	license.skipOnShallow	false	Skip the entire plugin execution silently
failOnShallow	license.failOnShallow	false	Fail the build with an error

When both skipOnShallow and failOnShallow are true, skipOnShallow takes precedence.

Recommended for CI / AI Agents

Set license.skipOnShallow=true in pipelines that use shallow clones to avoid widespread header rewrites from inaccurate year values.