P2toM2 is a tool from Eclipse SCADA (Releng) used to convert P2 repositories to Maven 2 repositories.
The source is in the git repository: http://git.eclipse.org/c/eclipsescada/org.eclipse.scada.releng.git/tree/org.eclipse.scada.releng.p2.to.maven
The most recent binary is at: http://download.eclipse.org/eclipsescada/releng/
java -jar p2tom2/plugins/org.eclipse.equinox.launcher*.jar -consoleLog file:config.properties <sourceP2Repository> [<validationRepositoryies>]
The source repository is as URI to the repository that is to be converted. This can be an HTTP or FILE based repository. Everything that P2 supports.
The validation repositories are only used in order to resolve dependencies. The content will not be mirrored. However if dependencies from the validation repositories are not mirrored and are not available later, you will run into dependency issues.
The configuration file is a plain java properties file. All properties defined here can also be set as system properties. In this case the system properties override the values from the file.