DataNucleus uses Subversion (SVN) for housing its source code. The DataNucleus SVN repository is hosted by SourceForge. You can check out from the SVN repository using

svn co https://datanucleus.svn.sourceforge.net/svnroot/datanucleus datanucleus

Please note that this will check out ALL code and all releases. What would be better is to check out "trunk" of all plugins. The SVN repository is divided into the following areas

• platform : The DataNucleus platform (core, enhancer, etc)
• test : End-to-end tests for DataNucleus products
• documentation : All documentation
• tools : Tools to aid the use of DataNucleus (Maven1 plugin, Maven2 plugin, etc)
• samples : Samples for use of DataNucleus products

Within platform the sub-projects are stored. These include

• core : the core of DataNucleus, required by all other sub-projects
• enhancer : DataNucleus enhancer
• cache : Level2 cache plugin supporting EHCache, OSCache, Coherence, SwarmCache
• java5 : Java5 extension plugin
• jdo.connector : JCA adapter for DataNucleus and JDO
• management : JMX management tools
• store.db4o : Persistence to DB4O datastores
• store.excel : Persistence to Excel documents
• store.ldap : Persistence to LDAP datastores
• store.rdbms : Persistence to RDBMS datastores
• store.rdbms.connectionpool : datasource pooling plugin supporting C3P0, DBCP, Proxool
• store.rdbms.spatial : Persistence of spatial types to RDBMS datastores
• store.xml : Persistence to XML documents

If you want to check the code out for latest versions, check out the "trunk" of all plugins.

The SVN repository is also browsable online via ViewVC.