Today I have released Hibernate ORM 5.0 (5.0.0.Final). This has been a long time coming and is the result
of the efforts of many folks. Thanks to everyone who helped us get here with fixes, bug reports, suggestions,
input and encouragement!
A lot of development has gone into 5.0. Here are the big points:
New bootstrap API
The venerable way to bootstrap Hibernate (build a SessionFactory) has been to use its Configuration class.
Configuration, historically, allowed users to iteratively add settings and mappings in any order and to query the
state of settings and mapping information in the middle of that process. Which meant that building the mapping
information could not effectively rely on any settings being available. This lead to many limitations and problems.
5.0 introduces a new bootstrapping API aimed at alleviating those limitations and problems, while allowing
better determinism and better integration. See the Bootstrap chapter in the User Guide for details on using
the new API.
Configuration is still available for use, although in a limited sense. Some of its methods have been removed. Under
the covers Configuration makes use of the new bootstrap API.
Hibernate Spatial is a project that has been around for a number of years. Karel Maesen has done an amazing job
Starting in 5.0 Hibernate Spatial is now part of the Hibernate project proper to allow it to better keep up with
upstream development. It is available as
org.hibernate:hibernate-spatial. If your application has need for
GIS data, we highly recommend giving hibernate-spatial a try.
Java 8 support
Well, ok.. not all of Java 8. Specifically we have added support for Java 8 Date and Time API in regards to easily mapping
attributes in your domain model using the Java 8 Date and Time API types to the database. This support is available
under the dedicated hibernate-java8 artifact (to isolate Java 8 dependencies). For additional information, see
the Basic Types chapter in the Domain Model Mapping Guide.
Expanded AUTO id generation support
JPA defines support for GenerationType#AUTO limited to just Number types. Starting in 5.0 Hibernate offers expandable support for a broader
set of types, including built-in support for both Number types (Integer, Long, etc) and UUID. Users are also free to plug
in custom strategies for interpreting GenerationType#AUTO via the new
Naming strategy split
NamingStrategy has been removed in favor of a better designed API. 2 distinct ones actually:
org.hibernate.boot.model.naming.ImplicitNamingStrategy- used whenever a table or column is not explicitly named to determine the name to use
org.hibernate.boot.model.naming.PhysicalNamingStrategy- used to convert a "logical name" (either implicit or explicit) name of a table or column
into a physical name (e.g. following corporate naming guidelines)
Attribute Converter support
5.0 offers significantly improved support for JPA 2.1 AttributeConverters:
- fully supported for non-@Enumerated enum values
- applicable in conjunction with @Nationalized support
- now called to handle null values
- settable in hbm.xml by using type="converter:fully.qualified.AttributeConverterName"
- integrated with hibernate-envers
- collection values, map keys
- support for conversion of parameterized types
Better "bulk id table" support
Support for "bulk id tables" has been completely redesigned to better fit what different databases support.
The transaction SPI underwent a major redesign as part of 5.0 as well. From a user perspective this generally
only comes into view in terms of configuration. Previously applications would work with the different backend
transaction stratagies directly via the
org.hibernate.Transaction API. In 5.0 a level of indirection has been
added here. The API implementation of
org.hibernate.Transaction is always the same now. On the backend, the
org.hibernate.Transaction impl talks to a
org.hibernate.resource.transaction.TransactionCoordinator which represents
the "transactional context" for a given Session according to the backend transaction strategy. Users generally do not
need to care about the distinction.
The change is noted here because it might affect your bootstrap configuration. Whereas previously applications would
hibernate.transaction.factory_class and refer to a
with 5.0 the new contract is
org.hibernate.resource.transaction.TransactionCoordinatorBuilder and is specified using the
hibernate.transaction.coordinator_class setting. See
JavaDocs for additional details.
The following short-names are recognized:
jdbc::(the default) says to use JDBC-based transactions (
jta::says to use JTA-based transactions (
See the User Guide for additional details.
5.0 offers much improvement in the area of schema tooling (export, validation and migration).
Typed Session API
Hibernate's native APIs (Session, etc) have been updated to be typed. No more casting!
Improved OSGi support
Really this started with a frustration over the fragility of hibernate-osgi tests. The first piece was a better testing setup using
Pax Exam and Karaf. This lead to us generating (and now publishing!) a Hibernate Karaf features file.
OSGi support has undergone some general improvement as well thanks to feedback from some Karaf and Pax developers and users.
See the Getting Started Guide for additional details on using the new Karaf features file.
Improved bytrecode enhancement capabilities
- dirty tracking
- bidirectional association management
- lazy loading
Work on documentation
A lot of work has gone into the documentation for 5.0. Its still not complete (is documentation ever "complete"?), but it is much improved.
See the revamped http://hibernate.org/orm/documentation/5.0[documentation page] for details.
For now the plan is to publish the release bundles (zip and tgz) to BinTray. We will continue to publish to SourceForge as well. For the time being
we will publish the bundles to both.
Ultimately we will start to publish the "maven" artifacts there as well.
This is all a work in progress.
How to get it
See http://hibernate.atlassian.net/projects/HHH/versions/20851 for the complete list of changes.
See http://hibernate.org/orm/downloads/ for information on obtaining the releases.