13.5. Hibernate Services
13.5.1. About Hibernate Services Copy linkLink copied to clipboard!
13.5.2. About Service Contracts Copy linkLink copied to clipboard!
org.hibernate.service.Service. Hibernate uses this internally for some basic type safety.
org.hibernate.service.spi.Startable and org.hibernate.service.spi.Stoppable interfaces to receive notifications of being started and stopped. Another optional service contract is org.hibernate.service.spi.Manageable which marks the service as manageable in JMX provided the JMX integration is enabled.
13.5.3. Types of Service Dependencies Copy linkLink copied to clipboard!
- @
org.hibernate.service.spi.InjectService - Any method on the service implementation class accepting a single parameter and annotated with @
InjectServiceis considered requesting injection of another service.By default the type of the method parameter is expected to be the service role to be injected. If the parameter type is different than the service role, theserviceRoleattribute of theInjectServiceshould be used to explicitly name the role.By default injected services are considered required, that is the start up will fail if a named dependent service is missing. If the service to be injected is optional, therequiredattribute of theInjectServiceshould be declared asfalse(default istrue). org.hibernate.service.spi.ServiceRegistryAwareService- The second approach is a pull approach where the service implements the optional service interface
org.hibernate.service.spi.ServiceRegistryAwareServicewhich declares a singleinjectServicesmethod.During startup, Hibernate will inject theorg.hibernate.service.ServiceRegistryitself into services which implement this interface. The service can then use theServiceRegistryreference to locate any additional services it needs.
13.5.4. The ServiceRegistry Copy linkLink copied to clipboard!
13.5.4.1. About the ServiceRegistry Copy linkLink copied to clipboard!
org.hibernate.service.ServiceRegistry interface. The main purpose of a service registry is to hold, manage and provide access to services.
org.hibernate.service.ServiceRegistryBuilder to build a org.hibernate.service.ServiceRegistry instance.
Example 13.21. Use ServiceRegistryBuilder to create a ServiceRegistry
ServiceRegistryBuilder registryBuilder = new ServiceRegistryBuilder( bootstrapServiceRegistry );
ServiceRegistry serviceRegistry = registryBuilder.buildServiceRegistry();
ServiceRegistryBuilder registryBuilder = new ServiceRegistryBuilder( bootstrapServiceRegistry );
ServiceRegistry serviceRegistry = registryBuilder.buildServiceRegistry();
13.5.5. Custom Services Copy linkLink copied to clipboard!
13.5.5.1. About Custom Services Copy linkLink copied to clipboard!
org.hibernate.service.ServiceRegistry is built it is considered immutable; the services themselves might accept re-configuration, but immutability here means adding/replacing services. So another role provided by the org.hibernate.service.ServiceRegistryBuilder is to allow tweaking of the services that will be contained in the org.hibernate.service.ServiceRegistry generated from it.
org.hibernate.service.ServiceRegistryBuilder about custom services.
- Implement a
org.hibernate.service.spi.BasicServiceInitiatorclass to control on-demand construction of the service class and add it to theorg.hibernate.service.ServiceRegistryBuildervia itsaddInitiatormethod. - Just instantiate the service class and add it to the
org.hibernate.service.ServiceRegistryBuildervia itsaddServicemethod.
Example 13.22. Use ServiceRegistryBuilder to Replace an Existing Service with a Custom Service
13.5.6. The Bootstrap Registry Copy linkLink copied to clipboard!
13.5.6.1. About the Boot-strap Registry Copy linkLink copied to clipboard!
ClassLoaderService which is a perfect example. Even resolving configuration files needs access to class loading services (resource look ups). This is the root registry (no parent) in normal use.
org.hibernate.service.BootstrapServiceRegistryBuilder class.
13.5.6.2. Using BootstrapServiceRegistryBuilder Copy linkLink copied to clipboard!
Example 13.23. Using BootstrapServiceRegistryBuilder
13.5.6.3. BootstrapRegistry Services Copy linkLink copied to clipboard!
org.hibernate.service.classloading.spi.ClassLoaderService
- the ability to locate application classes
- the ability to locate integration classes
- the ability to locate resources (properties files, xml files, etc)
- the ability to load
java.util.ServiceLoader
Note
org.hibernate.integrator.spi.IntegratorService
java.util.ServiceLoader capability provided by the org.hibernate.service.classloading.spi.ClassLoaderService in order to discover implementations of the org.hibernate.integrator.spi.Integrator contract.
/META-INF/services/org.hibernate.integrator.spi.Integrator and make it available on the classpath.
java.util.ServiceLoader mechanism. It lists, one per line, the fully qualified names of classes which implement the org.hibernate.integrator.spi.Integrator interface.
13.5.7. The SessionFactory Registry Copy linkLink copied to clipboard!
13.5.7.1. SessionFactory Registry Copy linkLink copied to clipboard!
org.hibernate.SessionFactory, the instances of services in this group explicitly belong to a single org.hibernate.SessionFactory.
org.hibernate.SessionFactory to be initiated. This special registry is org.hibernate.service.spi.SessionFactoryServiceRegistry
13.5.7.2. SessionFactory Services Copy linkLink copied to clipboard!
org.hibernate.event.service.spi.EventListenerRegistry
- Description
- Service for managing event listeners.
- Initiator
org.hibernate.event.service.internal.EventListenerServiceInitiator- Implementations
org.hibernate.event.service.internal.EventListenerRegistryImpl
13.5.8. Integrators Copy linkLink copied to clipboard!
13.5.8.1. Integrators Copy linkLink copied to clipboard!
org.hibernate.integrator.spi.Integrator is intended to provide a simple means for allowing developers to hook into the process of building a functioning SessionFactory. The org.hibernate.integrator.spi.Integrator interface defines 2 methods of interest: integrate allows us to hook into the building process; disintegrate allows us to hook into a SessionFactory shutting down.
Note
org.hibernate.integrator.spi.Integrator, an overloaded form of integrate accepting a org.hibernate.metamodel.source.MetadataImplementor instead of org.hibernate.cfg.Configuration. This form is intended for use with the new metamodel code scheduled for completion in 5.0.
13.5.8.2. Integrator use-cases Copy linkLink copied to clipboard!
org.hibernate.integrator.spi.Integrator right now are registering event listeners and providing services (see org.hibernate.integrator.spi.ServiceContributingIntegrator). With 5.0 we plan on expanding that to allow altering the metamodel describing the mapping between object and relational models.
Example 13.24. Registering event listeners