From 3822aefec924204f2dc5579d239f7243021f9bfd Mon Sep 17 00:00:00 2001
From: Steve Ebersole <steve@hibernate.org>
Date: Tue, 23 Apr 2024 21:11:39 -0500
Subject: [PATCH] HHH-18003 - Create a PersistenceUnitDescriptor wrapper around
 JPA 3.2 PersistenceConfiguration

---
 .../jpa/HibernatePersistenceProvider.java     |   9 +-
 .../PersistenceConfigurationDescriptor.java   | 136 ++++++++++++++++++
 2 files changed, 143 insertions(+), 2 deletions(-)
 create mode 100644 hibernate-core/src/main/java/org/hibernate/jpa/boot/spi/PersistenceConfigurationDescriptor.java

diff --git a/hibernate-core/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java b/hibernate-core/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java
index e6d495ac7b..e810f961a2 100644
--- a/hibernate-core/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java
+++ b/hibernate-core/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java
@@ -19,6 +19,7 @@ import jakarta.persistence.spi.ProviderUtil;
 
 import org.hibernate.boot.registry.classloading.spi.ClassLoaderService;
 import org.hibernate.jpa.boot.internal.ParsedPersistenceXmlDescriptor;
+import org.hibernate.jpa.boot.spi.PersistenceConfigurationDescriptor;
 import org.hibernate.jpa.boot.internal.PersistenceXmlParser;
 import org.hibernate.jpa.boot.spi.Bootstrap;
 import org.hibernate.jpa.boot.spi.EntityManagerFactoryBuilder;
@@ -197,8 +198,12 @@ public class HibernatePersistenceProvider implements PersistenceProvider {
 
 	@Override
 	public EntityManagerFactory createEntityManagerFactory(PersistenceConfiguration configuration) {
-		// todo (jpa 3.2) : implement this
-		throw new UnsupportedOperationException( "Not yet implemented" );
+		final EntityManagerFactoryBuilder builder = getEntityManagerFactoryBuilder(
+				new PersistenceConfigurationDescriptor( configuration ),
+				Collections.emptyMap(),
+				HibernatePersistenceProvider.class.getClassLoader()
+		);
+		return builder.build();
 	}
 
 	@Override
diff --git a/hibernate-core/src/main/java/org/hibernate/jpa/boot/spi/PersistenceConfigurationDescriptor.java b/hibernate-core/src/main/java/org/hibernate/jpa/boot/spi/PersistenceConfigurationDescriptor.java
new file mode 100644
index 0000000000..9e739babcf
--- /dev/null
+++ b/hibernate-core/src/main/java/org/hibernate/jpa/boot/spi/PersistenceConfigurationDescriptor.java
@@ -0,0 +1,136 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html.
+ */
+package org.hibernate.jpa.boot.spi;
+
+import java.net.URL;
+import java.util.List;
+import java.util.Properties;
+
+import org.hibernate.bytecode.enhance.spi.EnhancementContext;
+import org.hibernate.bytecode.spi.ClassTransformer;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.internal.util.collections.CollectionHelper;
+import org.hibernate.jpa.HibernatePersistenceProvider;
+
+import jakarta.persistence.PersistenceConfiguration;
+import jakarta.persistence.SharedCacheMode;
+import jakarta.persistence.ValidationMode;
+import jakarta.persistence.spi.PersistenceUnitTransactionType;
+
+/**
+ * PersistenceUnitDescriptor wrapper around {@linkplain PersistenceConfiguration}
+ *
+ * @author Steve Ebersole
+ */
+public class PersistenceConfigurationDescriptor implements PersistenceUnitDescriptor {
+	private final PersistenceConfiguration persistenceConfiguration;
+
+	private final Properties properties;
+	private final List<String> managedClassNames;
+
+	public PersistenceConfigurationDescriptor(PersistenceConfiguration persistenceConfiguration) {
+		this.persistenceConfiguration = persistenceConfiguration;
+
+		this.properties = CollectionHelper.asProperties( persistenceConfiguration.properties() );
+		this.managedClassNames = persistenceConfiguration.managedClasses().stream().map( Class::getName ).toList();
+	}
+
+	@Override
+	public Properties getProperties() {
+		return properties;
+	}
+
+	@Override
+	public String getName() {
+		return persistenceConfiguration.name();
+	}
+
+	@Override
+	public String getProviderClassName() {
+		return persistenceConfiguration.provider();
+	}
+
+	@Override
+	public boolean isUseQuotedIdentifiers() {
+		return properties.get( AvailableSettings.GLOBALLY_QUOTED_IDENTIFIERS ) == Boolean.TRUE;
+	}
+
+	@Override
+	public boolean isExcludeUnlistedClasses() {
+		// because we do not know the root url nor jar files we cannot do scanning
+		return true;
+	}
+
+	@SuppressWarnings("removal")
+	@Override
+	public PersistenceUnitTransactionType getTransactionType() {
+		return switch ( persistenceConfiguration.transactionType() ) {
+			case JTA -> PersistenceUnitTransactionType.JTA;
+			case RESOURCE_LOCAL -> PersistenceUnitTransactionType.RESOURCE_LOCAL;
+		};
+	}
+
+	@Override
+	public ValidationMode getValidationMode() {
+		return persistenceConfiguration.validationMode();
+	}
+
+	@Override
+	public SharedCacheMode getSharedCacheMode() {
+		return persistenceConfiguration.sharedCacheMode();
+	}
+
+	@Override
+	public List<String> getManagedClassNames() {
+		return managedClassNames;
+	}
+
+	@Override
+	public List<String> getMappingFileNames() {
+		return persistenceConfiguration.mappingFiles();
+	}
+
+	@Override
+	public Object getNonJtaDataSource() {
+		return persistenceConfiguration.nonJtaDataSource();
+	}
+
+	@Override
+	public Object getJtaDataSource() {
+		return persistenceConfiguration.jtaDataSource();
+	}
+
+	@Override
+	public ClassLoader getClassLoader() {
+		return HibernatePersistenceProvider.class.getClassLoader();
+	}
+
+	@Override
+	public ClassLoader getTempClassLoader() {
+		return null;
+	}
+
+	@Override
+	public void pushClassTransformer(EnhancementContext enhancementContext) {
+
+	}
+
+	@Override
+	public ClassTransformer getClassTransformer() {
+		return null;
+	}
+
+	@Override
+	public URL getPersistenceUnitRootUrl() {
+		return null;
+	}
+
+	@Override
+	public List<URL> getJarFileUrls() {
+		return null;
+	}
+}