Introduction to XML Descriptors (ELUG)
For the latest EclipseLink documentation, please see http://www.eclipse.org/eclipselink/documentation/
This section introduces options specific to an XML descriptor.
For information on descriptor concepts and features common to more than one type of EclipseLink descriptors, see Introduction to Descriptors.
XML Descriptor Concepts
XML descriptors describe Java objects that you map to simple and complex types defined by an XML schema document (XSD).
Using XML descriptors in an XML project, you can configure XML mappings (see XML Mapping Types), in memory, to XML elements defined by an XSD.
For more information, see the following:
XML Descriptors and Aggregation
When working with descriptors for a parent (source) and a child (target) objects, you have to accomplish the following:
- if the source object exists, then you must ensure that the target object also exists;
- if the source object is destroyed, then you must ensure that the target object is also destroyed.
For more information, see Descriptors and Aggregation.
In your XML project, designate the descriptors for the source and target objects to reflect this relationship as Composite Descriptors in XML Projects.
Composite Descriptors in XML Projects
In an XML project, descriptors are always composites.
Because XML descriptors are always composites, you can configure inheritance for an XML descriptor without considering its type (see Descriptors and Inheritance).