DataNucleus supports persistence to heterogeneous datastores and this plugin provides persistence to XML.
'org.datanucleus:datanucleus-xml:2.0.3'
<dependency>
<groupId>org.datanucleus</groupId>
<artifactId>datanucleus-xml</artifactId>
<version>2.0.3</version>
</dependency>
<dependency org="org.datanucleus" name="datanucleus-xml" rev="2.0.3"/>
"org.datanucleus", "datanucleus-xml", "2.0.3"