To improve the experience, you can optionally include metadata about the extension in an XML file, bundled within the JAR file itself.

The name of the extension metadata file has to be datacleaner-extension.xml and be placed in the root directory of the JAR file. Here's an example of how the file looks like:

			<extension xmlns="http://eobjects.org/datacleaner/extension/1.0">
			  <name>My extension</name>
			  <package>path.to.extension</package>
			  <description>This is an example extension. I should put a short description here.</description>
			  <icon>path/to/extension/ExtensionIcon.png</icon>
			  <author>John Doe</author>
			  <url>https://datacleaner.org/extensions</url>
			  <version>1.0</version>
			</extension>
		

The added value of this metadata is that DataCleaner can expose this information to the user and also use it to manage updates of the extension etc. The metadata file is however, completely optional.