DataNucleus supports persistence to heterogeneous datastores and this plugin provides persistence to Excel.
'org.datanucleus:datanucleus-excel:3.2.0-release'
<dependency>
<groupId>org.datanucleus</groupId>
<artifactId>datanucleus-excel</artifactId>
<version>3.2.0-release</version>
</dependency>
<dependency org="org.datanucleus" name="datanucleus-excel" rev="3.2.0-release"/>
"org.datanucleus", "datanucleus-excel", "3.2.0-release"