11.5.5. Custom Services

11.5.5.1. About Custom Services

Once a 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.
There are 2 means to tell a org.hibernate.service.ServiceRegistryBuilder about custom services.
  • Implement a org.hibernate.service.spi.BasicServiceInitiator class to control on-demand construction of the service class and add it to the org.hibernate.service.ServiceRegistryBuilder via its addInitiator method.
  • Just instantiate the service class and add it to the org.hibernate.service.ServiceRegistryBuilder via its addService method.
Either approach the adding a service approach or the adding an initiator approach are valid for extending a registry (adding new service roles) and overriding services (replacing service implementations).

Example 11.22. Use ServiceRegistryBuilder to Replace an Existing Service with a Custom Service

   ServiceRegistryBuilder registryBuilder = new ServiceRegistryBuilder( bootstrapServiceRegistry );
   serviceRegistryBuilder.addService( JdbcServices.class, new FakeJdbcService() ); 
   ServiceRegistry serviceRegistry = registryBuilder.buildServiceRegistry();


   public class FakeJdbcService implements JdbcServices{

       @Override
       public ConnectionProvider getConnectionProvider() {
           return null;
       }

       @Override
       public Dialect getDialect() {
           return null;
       }

       @Override
       public SqlStatementLogger getSqlStatementLogger() {
           return null;
       }

       @Override
       public SqlExceptionHelper getSqlExceptionHelper() {
           return null;
       }

       @Override
       public ExtractedDatabaseMetaData getExtractedMetaDataSupport() {
           return null;
       }

       @Override
       public LobCreator getLobCreator(LobCreationContext lobCreationContext) {
           return null;
       }

       @Override
       public ResultSetWrapper getResultSetWrapper() {
           return null;
       }

       @Override
       public JdbcEnvironment getJdbcEnvironment() {
           return null;
       }
   }