Is there a JPA provider which stores in XML format and not for a RDBMS?

DataNucleues for example does it but I don't like the preprocessing (their JPA implementation is based on JDO). Are there other alternatives? The format of the XML-file doesn't really matter.

开发者_StackOverflow社区We use JPA already and store to a RDBMS. I don't need new design approach but just if there is such a solution to persist in XML. My question is not "Is it a good idea to persist with JPA to XML?"

EclipseLink includes both JPA and JAXB support to allow both database and XML mapping. You can use JAXB to serialize an object model to a file or stream. EclipseLink also has EIS support for non-relational databases including XML data sources (an XML file adapter is included).

In general if you are just looking for a light weight database, I would recommend an embedded Java database such as Derby or HSQL.