@Target(value={METHOD,FIELD})
@Retention(value=RUNTIME)
public @interface XmlValueExtension
If XmlValueExtension annotation is used, there is no inheritance restriction.
Using XmlValueExtension provides a way how to achieve backward compatibility with EclipseLink 2.5.x and before.
When using xml bindings with XmlValue property, it has same behavior as when XmlValueExtension is used. It means that there is no need to specify XmlValueExtension in xml, because the behavior is provided by default.
XmlValue