The mappedBy argument indicates that the relationship is owned by the resident field. Map one direction of the relationship, in this case the employee property on the Address entity, by inserting the annotation in the Employee entity: Address residence To create the one-to-one and embedded mapping:Įnsure that the accessor type FIELD has been defined at the package level, as described in Section 7.2.1.1, "Task 1: Define the Accessor Type and Import Packages". Because this relationship is bidirectional, that is, Employee points to Address, which must point back to Employee, it uses the TopLink extension to represent the back-pointer. This is considered a one-to-one mapping because the employee can be associated with only one address. This example shows how to map the Employee entity to the Address entity and then back to the Employee entity. The JPA and annotations indicate that only one instance of the source entity is able to refer to the same target entity instance. It completely replaces the annotation metadata, which is useful when you want to map to different XML representations.įor more information about how to use XML data representation, see Section 7.4, "Main Tasks for Using XML Metadata Representation to Override JAXB Annotations".ħ.2.1.2.1 Mapping a One-to-One and Embedded Relationship ![]() In this way you do not introduce new compile time dependencies in the object model. You use the standard JAXB annotations, and use the XML metadata for the MOXy extensions. This is useful when:Īnnotations define version one of the XML representation, and you use XML metadata to change the metadata for future versions. It adds to the metadata supplied by annotations. Under these and similar circumstances, you can use an XML data representation by exposing the eclipselink_oxm.xml file. Your object model already contains too many annotations-for example, from such services as JPA, Spring, JSR-303, and so on-and you want to specify the metadata elsewhere. You want to map an object model to multiple XML schemas, because JAXB rules preclude applying more than one mapping by using annotations. You want to specify metadata for a third-party class but do not have access to the source. JAXB/MOXy is not always the most effective way to map JPA to XML. It offers superior performance in several mapping scenarios.įor more information on MOXy, see the MOXy FAQ at: ![]() It allows you to combine MOXy mappings and the TopLink persistence framework to interact with your data through the J2EE connector architecture (JCA). It allows you to map your existing JPA models to industry standard schemas. It offers specific features, such as compound key mapping and mapping relationships with back-pointers to address critical JPA-to-XML mapping issues. This avoids static coupling of your mapped classes with a single XML schema. It allows you to map your own classes to your own XML schema, a process called "Meet in the Middle Mapping". Because MOXy represents the optimal JAXB implementation, you still implement it whether or not you explicitly use any of its extensions. You can use these latter annotations in conjunction with the standard annotations to extend the utility of JAXB. MOXy supports all the standard JAXB annotations in the package plus has its own extensions in the .annotations package. It allows you to map a Plain Old Java Objects (POJO) model to an XML schema, greatly enhancing your ability to create JPA-to-XML mappings. For more information on these annotations, see Oracle Fusion Middleware Java API Reference for Oracle TopLink.įor more information about JAXB, see "Java Architecture for XML Binding (JAXB)" at: ![]() These annotations are subclasses of the. JAXB uses an extended set of annotations to define the binding rules for Java-to-XML mapping. This service provides a means to access data exposed by JPA across computers, where the client computer might or might not be using Java. Both of these web service standards use JAXB as the default binding layer. Usually, an XML binding is used with JPA entities to create a data access service by optimizing a JAX-WS or JAX-RS implementation. In this way, applications can access the data in the XML from the object rather than using the Domain Object Model (DOM) or the Streaming API for XML (SAX) to retrieve the data from a direct representation of the XML itself. This process, called binding, represents information in an XML document as an object in computer memory. JAXB is a Java API that allows a Java program to access an XML document by presenting that document to the program in a Java format.
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