10.5. Facilities for vendor-specific extensions

The experts behind JDO recognize that vendors will wish to add functionality which goes beyond that detailed in the specification – typically mapping strategies – to their implementations. Furthermore, some of this functionality will require meta-data defined in the persistence descriptor and therefore available to the implementation at runtime. JDO defines the <extension> element specifically to facilitate the storage of vendor-specific, and therefore non-standard, information in the descriptor.

10.5.1. <extension>

jdo.dtd (extract)
 <!ELEMENT extension (extension)*> <!ATTLIST extension vendor-name CDATA #REQUIRED> <!ATTLIST extension key CDATA #IMPLIED> <!ATTLIST extension value CDATA #IMPLIED> ...

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