misc cleanups in the legacy id package

hibernate-core/src/main/java/org/hibernate/boot/model/internal/GeneratorParameters.java

@@ -19,13 +19,11 @@
 import org.hibernate.generator.GeneratorCreationContext;
 import org.hibernate.id.Configurable;
 import org.hibernate.id.OptimizableGenerator;
-import org.hibernate.id.PersistentIdentifierGenerator;
 import org.hibernate.id.enhanced.LegacyNamingStrategy;
 import org.hibernate.id.enhanced.SequenceStyleGenerator;
 import org.hibernate.id.enhanced.SingleNamingStrategy;
 import org.hibernate.mapping.Column;
 import org.hibernate.mapping.RootClass;
-import org.hibernate.mapping.Table;
 
 import jakarta.persistence.SequenceGenerator;
 import jakarta.persistence.TableGenerator;
@@ -40,10 +38,19 @@
 import static org.hibernate.id.OptimizableGenerator.IMPLICIT_NAME_BASE;
 import static org.hibernate.id.OptimizableGenerator.INCREMENT_PARAM;
 import static org.hibernate.id.OptimizableGenerator.INITIAL_PARAM;
+import static org.hibernate.id.PersistentIdentifierGenerator.CATALOG;
+import static org.hibernate.id.PersistentIdentifierGenerator.OPTIONS;
 import static org.hibernate.id.PersistentIdentifierGenerator.PK;
+import static org.hibernate.id.PersistentIdentifierGenerator.SCHEMA;
 import static org.hibernate.id.PersistentIdentifierGenerator.TABLE;
 import static org.hibernate.id.PersistentIdentifierGenerator.TABLES;
 import static org.hibernate.boot.BootLogging.BOOT_LOGGER;
+import static org.hibernate.id.enhanced.SequenceStyleGenerator.SEQUENCE_PARAM;
+import static org.hibernate.id.enhanced.TableGenerator.CONFIG_PREFER_SEGMENT_PER_ENTITY;
+import static org.hibernate.id.enhanced.TableGenerator.SEGMENT_COLUMN_PARAM;
+import static org.hibernate.id.enhanced.TableGenerator.SEGMENT_VALUE_PARAM;
+import static org.hibernate.id.enhanced.TableGenerator.TABLE_PARAM;
+import static org.hibernate.id.enhanced.TableGenerator.VALUE_COLUMN_PARAM;
 import static org.hibernate.internal.util.StringHelper.isNotBlank;
 import static org.hibernate.internal.util.collections.CollectionHelper.isNotEmpty;
 
@@ -111,16 +118,14 @@ static void collectBaselineProperties(
 			BiConsumer<String,String> parameterCollector,
 			ConfigurationService configService) {
 		//init the table here instead of earlier, so that we can get a quoted table name
-		//TODO: would it be better to simply pass the qualified table name, instead of
-		//	  splitting it up into schema/catalog/table names
-		final String tableName = identifierValue.getTable().getQuotedName( dialect );
-		parameterCollector.accept( TABLE, tableName );
+		//TODO: would it be better to simply pass the qualified table name,
+		//      instead of splitting it up into schema/catalog/table names
+		parameterCollector.accept( TABLE, identifierValue.getTable().getQuotedName( dialect ) );
 
 		//pass the column name (a generated id almost always has a single column)
 		if ( identifierValue.getColumnSpan() == 1 ) {
-			final Column column = (Column) identifierValue.getSelectables().get( 0 );
-			final String columnName = column.getQuotedName( dialect );
-			parameterCollector.accept( PK, columnName );
+			final var column = (Column) identifierValue.getSelectables().get( 0 );
+			parameterCollector.accept( PK, column.getQuotedName( dialect ) );
 		}
 
 		//pass the entity-name, if not a collection-id
@@ -139,25 +144,35 @@ static void collectBaselineProperties(
 			parameterCollector.accept( TABLES, identityTablesString( dialect, rootClass ) );
 		}
 		else {
-			parameterCollector.accept( TABLES, tableName );
-			parameterCollector.accept( IMPLICIT_NAME_BASE, tableName );
+			parameterCollector.accept( TABLES, identifierValue.getTable().getQuotedName( dialect ) );
+			parameterCollector.accept( IMPLICIT_NAME_BASE, identifierValue.getTable().getQuotedName( dialect ) );
 		}
 
 		parameterCollector.accept( CONTRIBUTOR_NAME,
 				identifierValue.getBuildingContext().getCurrentContributorName() );
 
-		final Map<String, Object> settings = configService.getSettings();
+		final var settings = configService.getSettings();
 		if ( settings.containsKey( PREFERRED_POOLED_OPTIMIZER ) ) {
-			parameterCollector.accept(
-					PREFERRED_POOLED_OPTIMIZER,
-					(String) settings.get( PREFERRED_POOLED_OPTIMIZER )
-			);
+			parameterCollector.accept( PREFERRED_POOLED_OPTIMIZER,
+					optimizerClassName( settings.get( PREFERRED_POOLED_OPTIMIZER ) ) );
+		}
+	}
+
+	private static String optimizerClassName(Object optimizerSetting) {
+		if  ( optimizerSetting instanceof String string ) {
+			return string;
+		}
+		else if ( optimizerSetting instanceof Class<?> clazz ) {
+			return clazz.getName();
+		}
+		else {
+			return optimizerSetting.toString();
 		}
 	}
 
 	public static String identityTablesString(Dialect dialect, RootClass rootClass) {
 		final var tables = new StringBuilder();
-		for ( Table table : rootClass.getIdentityTables() ) {
+		for ( var table : rootClass.getIdentityTables() ) {
 			tables.append( table.getQuotedName( dialect ) );
 			if ( !tables.isEmpty() ) {
 				tables.append( ", " );
@@ -188,67 +203,51 @@ public static void interpretTableGenerator(
 			IdentifierGeneratorDefinition.Builder definitionBuilder) {
 		definitionBuilder.setName( tableGeneratorAnnotation.name() );
 		definitionBuilder.setStrategy( org.hibernate.id.enhanced.TableGenerator.class.getName() );
-		definitionBuilder.addParam( org.hibernate.id.enhanced.TableGenerator.CONFIG_PREFER_SEGMENT_PER_ENTITY, "true" );
+		definitionBuilder.addParam( CONFIG_PREFER_SEGMENT_PER_ENTITY, "true" );
 
 		final String catalog = tableGeneratorAnnotation.catalog();
 		if ( isNotBlank( catalog ) ) {
-			definitionBuilder.addParam( PersistentIdentifierGenerator.CATALOG, catalog );
+			definitionBuilder.addParam( CATALOG, catalog );
 		}
 
 		final String schema = tableGeneratorAnnotation.schema();
 		if ( isNotBlank( schema ) ) {
-			definitionBuilder.addParam( PersistentIdentifierGenerator.SCHEMA, schema );
+			definitionBuilder.addParam( SCHEMA, schema );
 		}
 
 		final String table = tableGeneratorAnnotation.table();
 		if ( isNotBlank( table ) ) {
-			definitionBuilder.addParam( org.hibernate.id.enhanced.TableGenerator.TABLE_PARAM, table );
+			definitionBuilder.addParam( TABLE_PARAM, table );
 		}
 
 		final String pkColumnName = tableGeneratorAnnotation.pkColumnName();
 		if ( isNotBlank( pkColumnName ) ) {
-			definitionBuilder.addParam(
-					org.hibernate.id.enhanced.TableGenerator.SEGMENT_COLUMN_PARAM,
-					pkColumnName
-			);
+			definitionBuilder.addParam( SEGMENT_COLUMN_PARAM, pkColumnName );
 		}
 
 		final String pkColumnValue = tableGeneratorAnnotation.pkColumnValue();
 		if ( isNotBlank( pkColumnValue ) ) {
-			definitionBuilder.addParam(
-					org.hibernate.id.enhanced.TableGenerator.SEGMENT_VALUE_PARAM,
-					pkColumnValue
-			);
+			definitionBuilder.addParam( SEGMENT_VALUE_PARAM, pkColumnValue );
 		}
 
 		final String valueColumnName = tableGeneratorAnnotation.valueColumnName();
 		if ( isNotBlank( valueColumnName ) ) {
-			definitionBuilder.addParam(
-					org.hibernate.id.enhanced.TableGenerator.VALUE_COLUMN_PARAM,
-					valueColumnName
-			);
+			definitionBuilder.addParam( VALUE_COLUMN_PARAM, valueColumnName );
 		}
 
 		final String options = tableGeneratorAnnotation.options();
 		if ( isNotBlank( options ) ) {
-			definitionBuilder.addParam(
-					PersistentIdentifierGenerator.OPTIONS,
-					options
-			);
+			definitionBuilder.addParam( OPTIONS, options );
 		}
 
-		definitionBuilder.addParam(
-				INCREMENT_PARAM,
-				String.valueOf( tableGeneratorAnnotation.allocationSize() )
-		);
+		definitionBuilder.addParam( INCREMENT_PARAM,
+				String.valueOf( tableGeneratorAnnotation.allocationSize() ) );
 
-		// See comment on HHH-4884 wrt initialValue.  Basically initialValue is really the stated value + 1
-		definitionBuilder.addParam(
-				INITIAL_PARAM,
-				String.valueOf( tableGeneratorAnnotation.initialValue() + 1 )
-		);
+		// See comment on HHH-4884 wrt initialValue. Basically initialValue is really the stated value + 1
+		definitionBuilder.addParam( INITIAL_PARAM,
+				String.valueOf( tableGeneratorAnnotation.initialValue() + 1 ) );
 
-		// TODO : implement unique-constraint support
+		// TODO: implement unique constraint support
 		if ( isNotEmpty( tableGeneratorAnnotation.uniqueConstraints() ) ) {
 			BOOT_LOGGER.ignoringTableGeneratorConstraints( tableGeneratorAnnotation.name() );
 		}
@@ -263,31 +262,27 @@ public static void interpretSequenceGenerator(
 
 		final String catalog = sequenceGeneratorAnnotation.catalog();
 		if ( isNotBlank( catalog ) ) {
-			definitionBuilder.addParam( PersistentIdentifierGenerator.CATALOG, catalog );
+			definitionBuilder.addParam( CATALOG, catalog );
 		}
 
 		final String schema = sequenceGeneratorAnnotation.schema();
 		if ( isNotBlank( schema ) ) {
-			definitionBuilder.addParam( PersistentIdentifierGenerator.SCHEMA, schema );
+			definitionBuilder.addParam( SCHEMA, schema );
 		}
 
 		final String sequenceName = sequenceGeneratorAnnotation.sequenceName();
 		if ( isNotBlank( sequenceName ) ) {
-			definitionBuilder.addParam( SequenceStyleGenerator.SEQUENCE_PARAM, sequenceName );
+			definitionBuilder.addParam( SEQUENCE_PARAM, sequenceName );
 		}
 
-		definitionBuilder.addParam(
-				INCREMENT_PARAM,
-				String.valueOf( sequenceGeneratorAnnotation.allocationSize() )
-		);
-		definitionBuilder.addParam(
-				INITIAL_PARAM,
-				String.valueOf( sequenceGeneratorAnnotation.initialValue() )
-		);
+		definitionBuilder.addParam( INCREMENT_PARAM,
+				String.valueOf( sequenceGeneratorAnnotation.allocationSize() ) );
+		definitionBuilder.addParam( INITIAL_PARAM,
+				String.valueOf( sequenceGeneratorAnnotation.initialValue() ) );
 
 		final String options = sequenceGeneratorAnnotation.options();
 		if ( isNotBlank( options ) ) {
-			definitionBuilder.addParam( PersistentIdentifierGenerator.OPTIONS, options );
+			definitionBuilder.addParam( OPTIONS, options );
 		}
 	}
 }

hibernate-core/src/main/java/org/hibernate/cfg/MappingSettings.java

@@ -118,12 +118,20 @@ public interface MappingSettings {
 	String KEYWORD_AUTO_QUOTING_ENABLED = "hibernate.auto_quote_keyword";
 
 	/**
-	 * When a generator specifies an increment size and an optimizer was not explicitly
-	 * specified, which of the "pooled" optimizers should be preferred? Can specify an
-	 * optimizer short name or the name of a class which implements
-	 * {@link org.hibernate.id.enhanced.Optimizer}.
+	 * Specifies an {@linkplain org.hibernate.id.enhanced.Optimizer optimizer}
+	 * which should be used when a generator specifies an {@code allocationSize}
+	 * and no optimizer is not explicitly specified, either:
+	 * <ul>
+	 * <li>a class implementing {@link org.hibernate.id.enhanced.Optimizer},
+	 * <li>the name of a class implementing {@code Optimizer}, or</li>
+	 * <li>an {@linkplain StandardOptimizerDescriptor optimizer short name}.
+	 * </ul>
 	 *
 	 * @settingDefault {@link StandardOptimizerDescriptor#POOLED}
+	 *
+	 * @see org.hibernate.id.enhanced.PooledOptimizer
+	 * @see org.hibernate.id.enhanced.PooledLoOptimizer
+	 * @see org.hibernate.id.enhanced.HiLoOptimizer
 	 */
 	String PREFERRED_POOLED_OPTIMIZER = "hibernate.id.optimizer.pooled.preferred";
 

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

@@ -8,6 +8,8 @@
 
 import org.hibernate.internal.util.BytesHelper;
 
+import static java.lang.System.currentTimeMillis;
+
 /**
  * The base class for identifier generators that use a UUID algorithm. This
  * class implements the algorithm, subclasses define the identifier
@@ -34,7 +36,7 @@ public abstract class AbstractUUIDGenerator implements IdentifierGenerator {
 	}
 
 	private static short counter = (short) 0;
-	private static final int JVM = (int) ( System.currentTimeMillis() >>> 8 );
+	private static final int JVM = (int) ( currentTimeMillis() >>> 8 );
 
 	public AbstractUUIDGenerator() {
 	}
@@ -72,10 +74,10 @@ protected int getIP() {
 	 * Unique down to millisecond
 	 */
 	protected short getHiTime() {
-		return (short) ( System.currentTimeMillis() >>> 32 );
+		return (short) ( currentTimeMillis() >>> 32 );
 	}
 
 	protected int getLoTime() {
-		return (int) System.currentTimeMillis();
+		return (int) currentTimeMillis();
 	}
 }

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

@@ -8,7 +8,6 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import org.hibernate.HibernateException;
 import org.hibernate.Internal;
 import org.hibernate.boot.model.relational.Database;
 import org.hibernate.boot.model.relational.ExportableProducer;
@@ -131,32 +130,9 @@ public void addGeneratedValuePlan(GenerationPlan plan) {
 	}
 
 	@Override
-	public Object generate(SharedSessionContractImplementor session, Object object) throws HibernateException {
+	public Object generate(SharedSessionContractImplementor session, Object object) {
 		final Object context = generationContextLocator.locateGenerationContext( session, object );
-
-		final List<Object> generatedValues = compositeType.isMutable() ?
-				null :
-				new ArrayList<>( generationPlans.size() );
-		for ( GenerationPlan generationPlan : generationPlans ) {
-			final BeforeExecutionGenerator generator = generationPlan.getGenerator();
-			final Object generated;
-			if ( generator.generatedBeforeExecution( object, session ) ) {
-				final Object currentValue = generator.allowAssignedIdentifiers()
-						? compositeType.getPropertyValue( context, generationPlan.getPropertyIndex(), session )
-						: null;
-				generated = generator.generate( session, object, currentValue, INSERT );
-			}
-			else {
-				throw new IdentifierGenerationException( "Identity generation isn't supported for composite ids" );
-			}
-			if ( generatedValues != null ) {
-				generatedValues.add( generated );
-			}
-			else {
-				generationPlan.getInjector().set( context, generated );
-			}
-		}
-
+		final List<Object> generatedValues = generatedValues( session, object, context );
 		if ( generatedValues != null) {
 			final Object[] values = compositeType.getPropertyValues( context );
 			for ( int i = 0; i < generatedValues.size(); i++ ) {
@@ -169,16 +145,41 @@ public Object generate(SharedSessionContractImplementor session, Object object)
 		}
 	}
 
+	private List<Object> generatedValues(SharedSessionContractImplementor session, Object object, Object context) {
+		final List<Object> generatedValues =
+				compositeType.isMutable()
+						? null
+						: new ArrayList<>( generationPlans.size() );
+		for ( var generationPlan : generationPlans ) {
+			final var generator = generationPlan.getGenerator();
+			if ( !generator.generatedBeforeExecution( object, session ) ) {
+				throw new IdentifierGenerationException( "Identity generation isn't supported for composite ids" );
+			}
+			final Object currentValue =
+					generator.allowAssignedIdentifiers()
+							? compositeType.getPropertyValue( context, generationPlan.getPropertyIndex(), session )
+							: null;
+			final Object generated = generator.generate( session, object, currentValue, INSERT );
+			if ( generatedValues != null ) {
+				generatedValues.add( generated );
+			}
+			else {
+				generationPlan.getInjector().set( context, generated );
+			}
+		}
+		return generatedValues;
+	}
+
 	@Override
 	public void registerExportables(Database database) {
-		for ( GenerationPlan plan : generationPlans ) {
+		for ( var plan : generationPlans ) {
 			plan.registerExportables( database );
 		}
 	}
 
 	@Override
 	public void initialize(SqlStringGenerationContext context) {
-		for ( GenerationPlan plan : generationPlans ) {
+		for ( var plan : generationPlans ) {
 			plan.initialize( context );
 		}
 	}

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

@@ -38,21 +38,22 @@ public Object generate(SharedSessionContractImplementor session, Object obj) thr
 		final String sql = session.getJdbcServices().getJdbcEnvironment().getDialect().getSelectGUIDString();
 		try {
 			final var jdbcCoordinator = session.getJdbcCoordinator();
-			final var st = jdbcCoordinator.getStatementPreparer().prepareStatement( sql );
+			final var statement = jdbcCoordinator.getStatementPreparer().prepareStatement( sql );
+			final var resourceRegistry = jdbcCoordinator.getLogicalConnection().getResourceRegistry();
 			try {
-				final var rs = jdbcCoordinator.getResultSetReturn().extract( st, sql );
+				final var resultSet = jdbcCoordinator.getResultSetReturn().extract( statement, sql );
 				try {
-					if ( !rs.next() ) {
+					if ( !resultSet.next() ) {
 						throw new HibernateException( "The database returned no GUID identity value" );
 					}
-					return rs.getString( 1 );
+					return resultSet.getString( 1 );
 				}
 				finally {
-					jdbcCoordinator.getLogicalConnection().getResourceRegistry().release( rs, st );
+					resourceRegistry.release( resultSet, statement );
 				}
 			}
 			finally {
-				jdbcCoordinator.getLogicalConnection().getResourceRegistry().release( st );
+				resourceRegistry.release( statement );
 				jdbcCoordinator.afterStatementExecution();
 			}
 		}