HHH-8923 - Reconsider closing of ServiceRegistry instances

Conflicts:
	hibernate-core/src/main/java/org/hibernate/boot/registry/BootstrapServiceRegistryBuilder.java
	hibernate-core/src/main/java/org/hibernate/boot/registry/StandardServiceRegistryBuilder.java
	hibernate-core/src/main/java/org/hibernate/boot/registry/internal/BootstrapServiceRegistryImpl.java
	hibernate-core/src/main/java/org/hibernate/boot/registry/internal/StandardServiceRegistryImpl.java
	hibernate-core/src/main/java/org/hibernate/service/internal/AbstractServiceRegistryImpl.java
	hibernate-core/src/test/java/org/hibernate/connection/ConnectionCreatorTest.java

hibernate-core/src/main/java/org/hibernate/service/BootstrapServiceRegistryBuilder.java

@@ -45,6 +45,7 @@ public class BootstrapServiceRegistryBuilder {
 	private final LinkedHashSet<Integrator> providedIntegrators = new LinkedHashSet<Integrator>();
 	private List<ClassLoader> providedClassLoaders;
 	private ClassLoaderService providedClassLoaderService;
+	private boolean autoCloseRegistry = true;
 
 	/**
 	 * Add an {@link Integrator} to be applied to the bootstrap registry.
@@ -141,6 +142,35 @@ public class BootstrapServiceRegistryBuilder {
 	public BootstrapServiceRegistryBuilder withEnvironmentClassLoader(ClassLoader classLoader) {
 		return with( classLoader );
 	}
+	
+	/**
+	* By default, when a ServiceRegistry is no longer referenced by any other
+	* registries as a parent it will be closed.
+	* <p/>
+	* Some applications that explicitly build "shared registries" may want to
+	* circumvent that behavior.
+	* <p/>
+	* This method indicates that the registry being built should not be
+	* automatically closed. The caller agrees to take responsibility to
+	* close it themselves.
+	*
+	* @return this, for method chaining
+	*/
+	public BootstrapServiceRegistryBuilder disableAutoClose() {
+		this.autoCloseRegistry = false;
+		return this;
+	}
+
+	/**
+	* See the discussion on {@link #disableAutoClose}. This method enables
+	* the auto-closing.
+	*
+	* @return this, for method chaining
+	*/
+	public BootstrapServiceRegistryBuilder enableAutoClose() {
+		this.autoCloseRegistry = true;
+		return this;
+	}
 
 	/**
 	 * Build the bootstrap registry.
@@ -160,6 +190,6 @@ public class BootstrapServiceRegistryBuilder {
 				classLoaderService
 		);
 
-		return new BootstrapServiceRegistryImpl( classLoaderService, integratorService );
+		return new BootstrapServiceRegistryImpl( autoCloseRegistry, classLoaderService, integratorService );
 	}
 }

hibernate-core/src/main/java/org/hibernate/service/ServiceRegistryBuilder.java

@@ -66,6 +66,8 @@ public class ServiceRegistryBuilder {
 	private final Map settings;
 	private final List<BasicServiceInitiator> initiators = standardInitiatorList();
 	private final List<ProvidedService> providedServices = new ArrayList<ProvidedService>();
+	
+	private boolean autoCloseRegistry = true;
 
 	private final BootstrapServiceRegistry bootstrapServiceRegistry;
 
@@ -232,6 +234,34 @@ public class ServiceRegistryBuilder {
 		providedServices.add( new ProvidedService( serviceRole, service ) );
 		return this;
 	}
+	/**
+	* By default, when a ServiceRegistry is no longer referenced by any other
+	* registries as a parent it will be closed.
+	* <p/>
+	* Some applications that explicitly build "shared registries" may want to
+	* circumvent that behavior.
+	* <p/>
+	* This method indicates that the registry being built should not be
+	* automatically closed. The caller agrees to take responsibility to
+	* close it themselves.
+	*
+	* @return this, for method chaining
+	*/
+	public ServiceRegistryBuilder disableAutoClose() {
+		this.autoCloseRegistry = false;
+		return this;
+	}
+
+	/**
+	* See the discussion on {@link #disableAutoClose}. This method enables
+	* the auto-closing.
+	*
+	* @return this, for method chaining
+	*/
+	public ServiceRegistryBuilder enableAutoClose() {
+		this.autoCloseRegistry = true;
+		return this;
+	}
 
 	/**
 	 * Build the service registry accounting for all settings and service initiators and services.
@@ -250,7 +280,7 @@ public class ServiceRegistryBuilder {
 			}
 		}
 
-		return new StandardServiceRegistryImpl( bootstrapServiceRegistry, initiators, providedServices, settingsCopy );
+		return new StandardServiceRegistryImpl( autoCloseRegistry, bootstrapServiceRegistry, initiators, providedServices, settingsCopy );
 	}
 
 	/**

hibernate-core/src/main/java/org/hibernate/service/internal/AbstractServiceRegistryImpl.java

@@ -67,6 +67,7 @@ public abstract class AbstractServiceRegistryImpl
 	// assume 20 services for initial sizing
 	private final List<ServiceBinding> serviceBindingList = CollectionHelper.arrayList( 20 );
 
+	private boolean autoCloseRegistry;
 	private Set<ServiceRegistryImplementor> childRegistries;
 
 	@SuppressWarnings( {"UnusedDeclaration"})
@@ -74,16 +75,35 @@ public abstract class AbstractServiceRegistryImpl
 		this( (ServiceRegistryImplementor) null );
 	}
 
+	@SuppressWarnings( {"UnusedDeclaration"})
+	protected AbstractServiceRegistryImpl(boolean autoCloseRegistry) {
+		this( (ServiceRegistryImplementor) null, autoCloseRegistry );
+	}
+
 	protected AbstractServiceRegistryImpl(ServiceRegistryImplementor parent) {
+		this( parent, true );
+	}
+
+	protected AbstractServiceRegistryImpl(
+			ServiceRegistryImplementor parent,
+			boolean autoCloseRegistry) {
 		this.parent = parent;
+		this.autoCloseRegistry = autoCloseRegistry;
 		this.parent.registerChild( this );
 	}
 
 	public AbstractServiceRegistryImpl(BootstrapServiceRegistry bootstrapServiceRegistry) {
+		this( bootstrapServiceRegistry, true );
+	}
+
+	public AbstractServiceRegistryImpl(
+			BootstrapServiceRegistry bootstrapServiceRegistry,
+			boolean autoCloseRegistry) {
 		if ( ! ServiceRegistryImplementor.class.isInstance( bootstrapServiceRegistry ) ) {
 			throw new IllegalArgumentException( "Boot-strap registry was not " );
 		}
 		this.parent = (ServiceRegistryImplementor) bootstrapServiceRegistry;
+		this.autoCloseRegistry = autoCloseRegistry;
 		this.parent.registerChild( this );
 	}
 
@@ -332,11 +352,19 @@ public abstract class AbstractServiceRegistryImpl
 		}
 		childRegistries.remove( child );
 		if ( childRegistries.isEmpty() ) {
-			LOG.debug(
-					"Implicitly destroying ServiceRegistry on de-registration " +
-							"of all child ServiceRegistries"
-			);
-			destroy();
+			if ( autoCloseRegistry ) {
+				LOG.debug(
+						"Implicitly destroying ServiceRegistry on de-registration " +
+								"of all child ServiceRegistries"
+				);
+				destroy();
+			}
+			else {
+				LOG.debug(
+						"Skipping implicitly destroying ServiceRegistry on de-registration " +
+								"of all child ServiceRegistries"
+				);
+			}
 		}
 	}
 }

hibernate-core/src/main/java/org/hibernate/service/internal/BootstrapServiceRegistryImpl.java

@@ -61,6 +61,7 @@ public class BootstrapServiceRegistryImpl
 	
 	private static final LinkedHashSet<Integrator> NO_INTEGRATORS = new LinkedHashSet<Integrator>();
 	
+	private final boolean autoCloseRegistry;
 	private boolean active = true;
 
 	private final ServiceBinding<ClassLoaderService> classLoaderServiceBinding;
@@ -71,10 +72,19 @@ public class BootstrapServiceRegistryImpl
 	public BootstrapServiceRegistryImpl() {
 		this( new ClassLoaderServiceImpl(), NO_INTEGRATORS );
 	}
-
+	
 	public BootstrapServiceRegistryImpl(
 			ClassLoaderService classLoaderService,
 			IntegratorService integratorService) {
+		this( true, classLoaderService, integratorService );
+	}
+
+	public BootstrapServiceRegistryImpl(
+			boolean autoCloseRegistry,
+			ClassLoaderService classLoaderService,
+			IntegratorService integratorService) {
+		this.autoCloseRegistry = autoCloseRegistry;
+		
 		this.classLoaderServiceBinding = new ServiceBinding<ClassLoaderService>(
 				this,
 				ClassLoaderService.class,
@@ -92,7 +102,7 @@ public class BootstrapServiceRegistryImpl
 	public BootstrapServiceRegistryImpl(
 			ClassLoaderService classLoaderService,
 			LinkedHashSet<Integrator> providedIntegrators) {
-		this( classLoaderService, new IntegratorServiceImpl( providedIntegrators, classLoaderService ) );
+		this( true, classLoaderService, new IntegratorServiceImpl( providedIntegrators, classLoaderService ) );
 	}
 
 
@@ -189,8 +199,13 @@ public class BootstrapServiceRegistryImpl
 		}
 		childRegistries.remove( child );
 		if ( childRegistries.isEmpty() ) {
-			LOG.debug( "Implicitly destroying Boot-strap registry on de-registration " + "of all child ServiceRegistries" );
-			destroy();
+			if ( autoCloseRegistry ) {
+				LOG.debug( "Implicitly destroying Boot-strap registry on de-registration " + "of all child ServiceRegistries" );
+				destroy();
+			}
+			else {
+				LOG.debug( "Skipping implicitly destroying Boot-strap registry on de-registration " + "of all child ServiceRegistries" );
+			}
 		}
 	}
 

hibernate-core/src/main/java/org/hibernate/service/internal/StandardServiceRegistryImpl.java

@@ -48,7 +48,17 @@ public class StandardServiceRegistryImpl extends AbstractServiceRegistryImpl imp
 			List<BasicServiceInitiator> serviceInitiators,
 			List<ProvidedService> providedServices,
 			Map<?, ?> configurationValues) {
-		super( bootstrapServiceRegistry );
+		this( true, bootstrapServiceRegistry, serviceInitiators, providedServices, configurationValues );
+	}
+	
+	@SuppressWarnings( {"unchecked"})
+	public StandardServiceRegistryImpl(
+			boolean autoCloseRegistry,
+			BootstrapServiceRegistry bootstrapServiceRegistry,
+			List<BasicServiceInitiator> serviceInitiators,
+			List<ProvidedService> providedServices,
+			Map<?, ?> configurationValues) {
+		super( bootstrapServiceRegistry, autoCloseRegistry );
 
 		this.configurationValues = configurationValues;