HHH-18136 make it easier to write Generators which delegate to "old" id generation infrastructure

Signed-off-by: Gavin King <gavin@hibernate.org>

hibernate-core/src/main/java/org/hibernate/id/Configurable.java

@@ -9,6 +9,8 @@ package org.hibernate.id;
 import java.util.Properties;
 
 import org.hibernate.MappingException;
+import org.hibernate.boot.model.relational.Database;
+import org.hibernate.boot.model.relational.SqlStringGenerationContext;
 import org.hibernate.service.ServiceRegistry;
 import org.hibernate.type.Type;
 
@@ -21,12 +23,30 @@ import org.hibernate.type.Type;
 public interface Configurable {
 	/**
 	 * Configure this instance, given the value of parameters
-	 * specified by the user as {@code <param>} elements.
+	 * specified by the user as XML {@code <param>} elements and
+	 * {@link org.hibernate.annotations.Parameter @Parameter}
+	 * annotations.
+	 * <p>
 	 * This method is called just once, following instantiation.
+	 * If this instance also implements {@code ExportableProducer},
+	 * then this method is always called before
+	 * {@link org.hibernate.boot.model.relational.ExportableProducer#registerExportables(Database)},
 	 *
 	 * @param type The id property type descriptor
 	 * @param params param values, keyed by parameter name
 	 * @param serviceRegistry Access to service that may be needed.
 	 */
 	void configure(Type type, Properties params, ServiceRegistry serviceRegistry) throws MappingException;
+
+	/**
+	 * Initializes this instance, pre-generating SQL if necessary.
+	 * <p>
+	 * If this instance also implements {@code ExportableProducer},
+	 * then this method is always called after
+	 * {@link org.hibernate.boot.model.relational.ExportableProducer#registerExportables(Database)},
+	 * and before first use.
+	 *
+	 * @param context A context to help generate SQL strings
+	 */
+	default void initialize(SqlStringGenerationContext context) {}
 }

hibernate-core/src/main/java/org/hibernate/id/IdentifierGenerator.java

@@ -113,18 +113,6 @@ public interface IdentifierGenerator extends BeforeExecutionGenerator, Exportabl
 	@Override
 	default void registerExportables(Database database) {}
 
-	/**
-	 * Initializes this instance, in particular pre-generates
-	 * SQL as necessary.
-	 * <p>
-	 * This method is called after
-	 * {@link #registerExportables(Database)},
-	 * and before first use.
-	 *
-	 * @param context A context to help generate SQL strings
-	 */
-	default void initialize(SqlStringGenerationContext context) {}
-
 	/**
 	 * Generate a new identifier.
 	 *

hibernate-core/src/main/java/org/hibernate/id/factory/spi/CustomIdGeneratorCreationContext.java

@@ -15,4 +15,8 @@ import org.hibernate.generator.GeneratorCreationContext;
 public interface CustomIdGeneratorCreationContext extends GeneratorCreationContext {
 	IdentifierGeneratorFactory getIdentifierGeneratorFactory();
 	RootClass getRootClass();
+
+	// we could add these if it helps integrate old infrastructure
+//	Properties getParameters();
+//	SqlStringGenerationContext getSqlStringGenerationContext();
 }

hibernate-core/src/main/java/org/hibernate/internal/SessionFactoryImpl.java

@@ -68,6 +68,7 @@ import org.hibernate.engine.transaction.jta.platform.spi.JtaPlatform;
 import org.hibernate.event.spi.EventEngine;
 import org.hibernate.generator.Generator;
 import org.hibernate.graph.spi.RootGraphImplementor;
+import org.hibernate.id.Configurable;
 import org.hibernate.id.IdentifierGenerator;
 import org.hibernate.id.factory.IdentifierGeneratorFactory;
 import org.hibernate.integrator.spi.Integrator;
@@ -466,8 +467,8 @@ public class SessionFactoryImpl extends QueryParameterBindingTypeResolverImpl im
 							jdbcServices.getJdbcEnvironment().getDialect(),
 							(RootClass) model
 					);
-					if ( generator instanceof IdentifierGenerator ) {
+					if ( generator instanceof Configurable ) {
-						final IdentifierGenerator identifierGenerator = (IdentifierGenerator) generator;
+						final Configurable identifierGenerator = (Configurable) generator;
 						identifierGenerator.initialize( sqlStringGenerationContext );
 					}
 					if ( generator.allowAssignedIdentifiers() ) {

hibernate-core/src/main/java/org/hibernate/mapping/Component.java

@@ -34,8 +34,8 @@ import org.hibernate.dialect.Dialect;
 import org.hibernate.engine.spi.Mapping;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.id.CompositeNestedGeneratedValueGenerator;
+import org.hibernate.id.Configurable;
 import org.hibernate.id.IdentifierGenerationException;
-import org.hibernate.id.IdentifierGenerator;
 import org.hibernate.id.factory.IdentifierGeneratorFactory;
 import org.hibernate.internal.util.ReflectHelper;
 import org.hibernate.internal.util.collections.ArrayHelper;
@@ -784,8 +784,8 @@ public class Component extends SimpleValue implements MetaAttributable, Sortable
 
 		@Override
 		public void initialize(SqlStringGenerationContext context) {
-			if ( subgenerator instanceof IdentifierGenerator ) {
+			if ( subgenerator instanceof Configurable) {
-				( (IdentifierGenerator) subgenerator).initialize( context );
+				( (Configurable) subgenerator).initialize( context );
 			}
 		}
 	}

hibernate-core/src/main/java/org/hibernate/mapping/SimpleValue.java

@@ -405,19 +405,20 @@ public abstract class SimpleValue implements KeyValue {
 			IdentifierGeneratorFactory identifierGeneratorFactory,
 			Dialect dialect,
 			RootClass rootClass) throws MappingException {
-		if ( generator != null ) {
+		getTable().setIdentifierValue( this );
-			return generator;
+
-		}
+		if ( generator == null ) {
-		else if ( customIdGeneratorCreator != null ) {
+			if ( customIdGeneratorCreator != null ) {
-			generator = customIdGeneratorCreator.createGenerator(
+				generator = customIdGeneratorCreator.createGenerator(
-					new IdGeneratorCreationContext( identifierGeneratorFactory, null, null, rootClass )
+						new IdGeneratorCreationContext( identifierGeneratorFactory, null, null, rootClass )
-			);
+				);
-			return generator;
+			}
-		}
+			else {
-		else {
+				generator = createLegacyIdentifierGenerator(this, identifierGeneratorFactory, dialect, null, null, rootClass );
-			generator = createLegacyIdentifierGenerator(this, identifierGeneratorFactory, dialect, null, null, rootClass );
+			}
-			return generator;
 		}
+
+		return generator;
 	}
 
 	public boolean isUpdateable() {
@@ -1134,5 +1135,22 @@ public abstract class SimpleValue implements KeyValue {
 		public Property getProperty() {
 			return rootClass.getIdentifierProperty();
 		}
+
+		// we could add these if it helps integrate old infrastructure
+//		@Override
+//		public Properties getParameters() {
+//			final Value value = getProperty().getValue();
+//			if ( !value.isSimpleValue() ) {
+//				throw new IllegalStateException( "not a simple-valued property" );
+//			}
+//			final Dialect dialect = getDatabase().getDialect();
+//			return collectParameters( (SimpleValue) value, dialect, defaultCatalog, defaultSchema, rootClass );
+//		}
+//
+//		@Override
+//		public SqlStringGenerationContext getSqlStringGenerationContext() {
+//			final Database database = getDatabase();
+//			return fromExplicit( database.getJdbcEnvironment(), database, defaultCatalog, defaultSchema );
+//		}
 	}
 }

hibernate-core/src/main/java/org/hibernate/persister/collection/AbstractCollectionPersister.java

@@ -52,6 +52,7 @@ import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.engine.spi.SubselectFetch;
 import org.hibernate.generator.BeforeExecutionGenerator;
 import org.hibernate.generator.Generator;
+import org.hibernate.id.Configurable;
 import org.hibernate.id.IdentifierGenerator;
 import org.hibernate.internal.FilterAliasGenerator;
 import org.hibernate.internal.FilterHelper;
@@ -605,8 +606,8 @@ public abstract class AbstractCollectionPersister
 		if ( generator.generatedOnExecution() ) {
 			throw new MappingException("must be an BeforeExecutionGenerator"); //TODO fix message
 		}
-		if ( generator instanceof IdentifierGenerator ) {
+		if ( generator instanceof Configurable ) {
-			( (IdentifierGenerator) generator ).initialize( context.getSqlStringGenerationContext() );
+			( (Configurable) generator ).initialize( context.getSqlStringGenerationContext() );
 		}
 		return (BeforeExecutionGenerator) generator;
 	}

hibernate-core/src/test/java/org/hibernate/orm/test/idgen/userdefined/NativeGenerator.java

@@ -0,0 +1,108 @@
+package org.hibernate.orm.test.idgen.userdefined;
+
+import org.hibernate.boot.model.relational.Database;
+import org.hibernate.boot.model.relational.ExportableProducer;
+import org.hibernate.boot.model.relational.SqlStringGenerationContext;
+import org.hibernate.dialect.Dialect;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.generator.BeforeExecutionGenerator;
+import org.hibernate.generator.EventType;
+import org.hibernate.generator.Generator;
+import org.hibernate.generator.OnExecutionGenerator;
+import org.hibernate.id.Configurable;
+import org.hibernate.id.PostInsertIdentityPersister;
+import org.hibernate.id.factory.IdentifierGeneratorFactory;
+import org.hibernate.id.factory.spi.CustomIdGeneratorCreationContext;
+import org.hibernate.id.insert.InsertGeneratedIdentifierDelegate;
+import org.hibernate.mapping.SimpleValue;
+import org.hibernate.service.ServiceRegistry;
+import org.hibernate.type.Type;
+
+import java.lang.reflect.Member;
+import java.util.EnumSet;
+import java.util.Properties;
+
+public class NativeGenerator
+        implements OnExecutionGenerator, BeforeExecutionGenerator, Configurable, ExportableProducer {
+
+    private final IdentifierGeneratorFactory factory;
+    private final String strategy;
+
+    private Generator generator;
+
+    public NativeGenerator(NativeId nativeId, Member member, CustomIdGeneratorCreationContext creationContext) {
+        factory = creationContext.getIdentifierGeneratorFactory();
+		strategy = creationContext.getDatabase().getDialect().getNativeIdentifierGeneratorStrategy();
+		SimpleValue value = (SimpleValue) creationContext.getProperty().getValue();
+        value.setIdentifierGeneratorStrategy(strategy);
+    }
+
+    @Override
+    public EnumSet<EventType> getEventTypes() {
+        return generator.getEventTypes();
+    }
+
+    @Override
+    public boolean generatedOnExecution() {
+        return generator.generatedOnExecution();
+    }
+
+    @Override
+    public void configure(Type type, Properties parameters, ServiceRegistry serviceRegistry) {
+        generator = factory.createIdentifierGenerator(strategy, type, parameters);
+        //TODO: should use this instead of the deprecated method, but see HHH-18135
+//        GenerationType generationType;
+//        switch (strategy) {
+//            case "identity":
+//                generationType = GenerationType.IDENTITY;
+//                break;
+//            case "sequence":
+//                generationType = GenerationType.SEQUENCE;
+//                break;
+//            default:
+//                throw new AssertionFailure("unrecognized strategy");
+//        }
+//        generator =
+//                factory.createIdentifierGenerator( generationType, strategy, strategy, type.getJavaTypeDescriptor(),
+//                        parameters, (a, b) -> null );
+    }
+
+    @Override
+    public void registerExportables(Database database) {
+        if ( generator instanceof ExportableProducer ) {
+            ((ExportableProducer) generator).registerExportables(database);
+        }
+    }
+
+    @Override
+    public void initialize(SqlStringGenerationContext context) {
+        if ( generator instanceof Configurable ) {
+            ((Configurable) generator).initialize(context);
+        }
+    }
+
+    @Override
+    public Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue, EventType eventType) {
+        return ((BeforeExecutionGenerator) generator).generate(session, owner, currentValue, eventType);
+    }
+
+    @Override
+    public boolean referenceColumnsInSql(Dialect dialect) {
+        return ((OnExecutionGenerator) generator).referenceColumnsInSql(dialect);
+    }
+
+    @Override
+    public boolean writePropertyValue() {
+        return ((OnExecutionGenerator) generator).writePropertyValue();
+    }
+
+    @Override
+    public String[] getReferencedColumnValues(Dialect dialect) {
+        return ((OnExecutionGenerator) generator).getReferencedColumnValues(dialect);
+    }
+
+    @Override
+    public InsertGeneratedIdentifierDelegate getGeneratedIdentifierDelegate(PostInsertIdentityPersister persister) {
+        return ((OnExecutionGenerator) generator).getGeneratedIdentifierDelegate(persister);
+    }
+}

hibernate-core/src/test/java/org/hibernate/orm/test/idgen/userdefined/NativeGeneratorTest.java

@@ -0,0 +1,21 @@
+package org.hibernate.orm.test.idgen.userdefined;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.Test;
+
+@SessionFactory
+@DomainModel(annotatedClasses = NativeGeneratorTest.NativeEntity.class)
+public class NativeGeneratorTest {
+	@Test void test(SessionFactoryScope scope) {
+		scope.inTransaction(s -> s.persist(new NativeEntity()));
+	}
+	@Entity
+	public static class NativeEntity {
+		@Id @NativeId
+		long id;
+	}
+}

hibernate-core/src/test/java/org/hibernate/orm/test/idgen/userdefined/NativeId.java

@@ -0,0 +1,14 @@
+package org.hibernate.orm.test.idgen.userdefined;
+
+import org.hibernate.annotations.IdGeneratorType;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.FIELD)
+@Retention(RetentionPolicy.RUNTIME)
+@IdGeneratorType(NativeGenerator.class)
+public @interface NativeId {
+}