CDO/Hibernate Store/Model Relational Mapping

The CDO Hibernate Store can use Teneo for the Model Relational mapping. Teneo generates a mapping for Hibernate on the basis of the ecore model and optional JPA annotations. JPA annotations can be specified directly in the model or in a separate xml.

Teneo supports all JPA annotations and many Hibernate extensions.

Annotations Format

The Teneo documentation has a detailed description of the format in which annotations can be specified. The main points are summarized here:

Teneo allows two ways to specify EJB3/JPA-like annotations:

1. using the java annotations syntax in EAnnotations (ecore and xsd) (examples)
2. a separate xml document (examples).

This page shows examples of both approaches.

JPA Annotations with a TYPE target can be used for EMF EClasses, annotations with METHOD and FIELD targets can be used for EStructuralFeatures. Note: JPA annotations relevant for a non-reference type java member can also be set on an EDataType.

JPA Annotations as EAnnotations

The EAnnotations should adhere to the following format:

• The source must be: teneo.jpa. You can also configure your own annotation source, see Teneo documentation for details.
• The key must be: appinfo or value

The page: here contains examples of JPA eannotations in Ecore or in a XML Schema file.

JPA Annotations in XSD, some examples

This annotation sets the inheritance mapping strategy for the Address to joined:

<xsd:complexType name="Address" abstract="true">
	<xsd:annotation>
		<xsd:appinfo source="teneo.jpa">@Inheritance(strategy=JOINED)</xsd:appinfo>
	</xsd:annotation>
 	<xsd:sequence>
		<xsd:element name="name" type="xsd:string"/>
	</xsd:sequence>
</xsd:complexType>

The following annotation specifies that the association does not need an index column:

<xsd:element name="containedItem" type="this:ContainedItem" maxOccurs="unbounded">
	<xsd:annotation>
		<xsd:appinfo source="teneo.jpa">@OneToMany(indexed=false)</xsd:appinfo>
	</xsd:annotation>
</xsd:element>

JPA Annotations in the Ecore Model Editor

To set an annotation in the ecore model using the Ecore Model Editor do the following:

1. open the model in the editor
2. right click on the model element (EClass, EStructuralFeature, etc.) on which you want to set a JPA annotation
3. do: New Child > EAnnotation
4. check in the properties view, there are two fields for the new EAnnotation: references and source. Set source to: teneo.jpa
5. right click on the new EAnnotation in the ecore model editor and do: New Child > Details Entry
6. click on the new detail entry, the properties view shows a key and value field. Enter the word 'value' in the key field and in the value field enter your annotation, for example: @Id or @Basic. Just as you would set it in Java.

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