Minimal Sample

To make a class persistence-capable a minimal description must be provided. The following file named /com/signsoft/Person.jdo provides the minimum metadata information for the class com.signsoft.Person:

<?xml version="1.0" encoding="UTF-8"?>
<jdo xmlns="http://java.sun.com/xml/ns/jdo/jdo" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/jdo/jdo http://java.sun.com/xml/ns/jdo/jdo_2_0.xsd">
  <package name="com.signsoft">
    <class name="Person"/>
  </package>
</jdo>

The pure mention of the class in this file means that the class is persistent. The persistent fields are specified using the default rules.