The following topics introduce the new and changed features of Oracle TopLink and other significant changes that are described in this guide, and provides pointers to additional information. This document is the new edition of the formerly titled Understanding Oracle TopLink.
Oracle TopLink 12c (12.2.1.2.0) includes the following new and changed features for this document.
Improved Collection Mapping to both XML and JSON—You can now map Collections to both XML and JSON by using the @XmlElementWrapper annotation as the JSON key. See Section 6.4.1, "Collection Mapping to both XML and JSON" for more information.
Marshalling and Unmarshalling a Subset of Attributes—you can now configure a subset of object attributes to be marshaled and unmarshaled by setting up attribute groups on the descriptor. See Section 6.3.3, "Marshalling and Unmarshalling a Subset of Attributes in MOXy" for more information.
@XmlInverseReference is Writable in Both Directions—The MOXy @XmlInverseReference annotation enables you to map a back pointer during the unmarshal operation. To map the pointer during the marshal operation, pair the @XmlInverseReference annotation with the @XmlElement annotation. See Section 6.3.4, "@XmlInverseReference is Writable in Both Directions" for more information.
JSON with Padding—JSON with Padding provides a way to request data from a server in a different domain, something prohibited by typical web browsers because of the same origin policy. See Section 6.5, "About JSON with Padding" for more information.
Improved Support for JAX-RS Implementations—The MOXyJsonProvider class can be used to enable EclipseLink JAXB (MOXy) as the JSON provider. This class can now be extended to make JAX-RS integration even easier. See Section 6.6, "Extending JAX-RS Implementations" for more information.
Heterogeneous Batch Writing—New persistence unit properties have been added to optimize transactions with multiple writes. See Section 7.9, "About Heterogeneous Batch Writing" for more information.
Binary Format Object Persistence— Section 7.10, "About Serialized Object Policy"
Auto-Tuning—The SessionTuner interface has been enhanced to facilitate template tuning configurations. Applications can now be easily tuned for development versus production, or for various deployment configurations. See Section 7.11, "About Auto-tuning" for more information.
TopLink Data Services Live Data—TopLink Data Services (TLDS) simplifies data access in modern HTML5, JavaScript, and mobile client applications by exposing a rich REST interface that provides access to enterprise Java Persistence. You can use TLDS to expose data stores, relational or NoSQL, with scalable persistence using server-side caching, validation, and security. See Section 7.12, "About TopLink Data Services Live Data" for more information.
For 12c (12.2.1.2.0), this guide has been updated in several ways. Following are the sections that have been added or changed.
Moved "New Features" from Chapter 1 to this chapter.
Removed the "Application Development" chapter.
Removed the section "Integrating with an Application Server."
Retitled Chapter 2, "Understanding Mappings" to Chapter 2, "Understanding Object-Relational and MOXy Internals."
Moved information about the persistence unit from Chapter 5 into its own chapter: Chapter 3, "Understanding the Persistence Unit."
Added new Section 4.8, "Extensible Entities" to describe that JPA entities and JAXB beans can be made extensible by adding or modifying mappings externally.
Information about descriptors now appears in Chapter 5, "Understanding Descriptors."
Information about mapping now appears in Chapter 6, "Understanding Mappings."
Added Section 7.8, "About Tenant Isolation" to describe the flexibility offered by EclipseLink for designing and implementing features for isolating tenants
Added Section 8.7, "Database Event Notification and Oracle CQN" which describes the API that allows the database to notify EclipseLink of database changes.
Consolidated information on cache clustering under Section 8.10, "Clustering and Cache Coordination."
Information about queries has been moved to Chapter 9, "Understanding Queries." Detailed information about JPQL query clauses which are part of standard JPA has been removed.
Information about the Expressions framework has been move to Chapter 10, "Understanding EclipseLink Expressions." Detailed information about database functions and operators that are part of standard JPA have been removed.
Information about NoSQL now appears in Chapter 11, "Understanding Non-relational Data Sources."
The "Understanding Performance Profiling and Monitoring" chapter has been removed.