unify timestamp generation in one generator instead of three

shows a nice feature of the constructor-based init

hibernate-core/src/main/java/org/hibernate/annotations/CreationTimestamp.java

@@ -13,7 +13,7 @@ import static java.lang.annotation.RetentionPolicy.RUNTIME;
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
-import org.hibernate.tuple.CreationTimestampGeneration;
+import org.hibernate.tuple.CurrentTimestampGeneration;
 
 /**
  * Specifies that the annotated field of property is a generated <em>creation timestamp</em>.
@@ -28,7 +28,7 @@ import org.hibernate.tuple.CreationTimestampGeneration;
  *
  * @see CurrentTimestamp
  */
-@ValueGenerationType(generatedBy = CreationTimestampGeneration.class)
+@ValueGenerationType(generatedBy = CurrentTimestampGeneration.class)
 @Retention(RUNTIME)
 @Target({ FIELD, METHOD })
 public @interface CreationTimestamp {

hibernate-core/src/main/java/org/hibernate/annotations/CurrentTimestamp.java

@@ -9,6 +9,7 @@ package org.hibernate.annotations;
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import org.hibernate.tuple.CurrentTimestampGeneration;
 import org.hibernate.tuple.GenerationTiming;
 
 import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
@@ -50,12 +51,13 @@ import static java.lang.annotation.RetentionPolicy.RUNTIME;
  * {@link java.time.YearMonth}, or
  * {@link java.time.ZonedDateTime}.
  *
- * @see CurrentTimestampGeneration
- *
- * @author Steve Ebersole
- *
  * @see UpdateTimestamp
  * @see CreationTimestamp
+ * @see CurrentTimestampGeneration
+ *
+ * @since 6.0
+ *
+ * @author Steve Ebersole
  */
 @ValueGenerationType(generatedBy = CurrentTimestampGeneration.class)
 @Retention(RUNTIME)

hibernate-core/src/main/java/org/hibernate/annotations/CurrentTimestampGeneration.java

@@ -1,62 +0,0 @@
-/*
- * 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.annotations;
-
-import org.hibernate.Internal;
-import org.hibernate.dialect.Dialect;
-import org.hibernate.tuple.AnnotationValueGeneration;
-import org.hibernate.tuple.GenerationTiming;
-import org.hibernate.tuple.TimestampGenerators;
-import org.hibernate.tuple.ValueGenerator;
-
-/**
- * Value generation strategy using the database {@code current_timestamp}
- * function or the JVM current instant.
- *
- * @see CurrentTimestamp
- *
- * @author Steve Ebersole
- */
-@Internal
-public class CurrentTimestampGeneration implements AnnotationValueGeneration<CurrentTimestamp> {
-	private GenerationTiming timing;
-	private ValueGenerator<?> generator;
-
-	@Override
-	public void initialize(CurrentTimestamp annotation, Class<?> propertyType) {
-		if ( annotation.source() == SourceType.VM ) {
-			// ValueGenerator is only used for in-VM generation
-			generator = TimestampGenerators.get( propertyType );
-		}
-		timing = annotation.timing();
-	}
-
-	@Override
-	public GenerationTiming getGenerationTiming() {
-		return timing;
-	}
-
-	@Override
-	public ValueGenerator<?> getValueGenerator() {
-		return generator;
-	}
-
-	@Override
-	public boolean referenceColumnInSql() {
-		return true;
-	}
-
-	@Override
-	public String getDatabaseGeneratedReferencedColumnValue() {
-		return "current_timestamp";
-	}
-
-	@Override
-	public String getDatabaseGeneratedReferencedColumnValue(Dialect dialect) {
-		return dialect.currentTimestamp();
-	}
-}

hibernate-core/src/main/java/org/hibernate/annotations/NoAttributeConverter.java

@@ -7,10 +7,14 @@
 package org.hibernate.annotations;
 
 import jakarta.persistence.AttributeConverter;
+import org.hibernate.Remove;
 
 /**
  * @author Steve Ebersole
+ *
+ * @deprecated this class is no longer used
  */
+@Deprecated(since= "6.2") @Remove
 public class NoAttributeConverter<O,R> implements AttributeConverter<O,R> {
 	@Override
 	public R convertToDatabaseColumn(Object attribute) {

hibernate-core/src/main/java/org/hibernate/annotations/Source.java

@@ -7,6 +7,7 @@
 package org.hibernate.annotations;
 
 import org.hibernate.Remove;
+import org.hibernate.tuple.SourceGeneration;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;

hibernate-core/src/main/java/org/hibernate/annotations/UpdateTimestamp.java

@@ -13,7 +13,7 @@ import static java.lang.annotation.RetentionPolicy.RUNTIME;
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
-import org.hibernate.tuple.UpdateTimestampGeneration;
+import org.hibernate.tuple.CurrentTimestampGeneration;
 
 /**
  * Specifies that the annotated field of property is a generated <em>update timestamp.</em>
@@ -28,7 +28,7 @@ import org.hibernate.tuple.UpdateTimestampGeneration;
  *
  * @author Gunnar Morling
  */
-@ValueGenerationType(generatedBy = UpdateTimestampGeneration.class)
+@ValueGenerationType(generatedBy = CurrentTimestampGeneration.class)
 @Retention(RUNTIME)
 @Target({ FIELD, METHOD })
 public @interface UpdateTimestamp {

hibernate-core/src/main/java/org/hibernate/boot/model/source/internal/hbm/ModelBinder.java

@@ -19,7 +19,7 @@ import java.util.Properties;
 import org.hibernate.AssertionFailure;
 import org.hibernate.FetchMode;
 import org.hibernate.annotations.Source;
-import org.hibernate.annotations.SourceGeneration;
+import org.hibernate.tuple.SourceGeneration;
 import org.hibernate.annotations.SourceType;
 import org.hibernate.boot.MappingException;
 import org.hibernate.boot.jaxb.Origin;

hibernate-core/src/main/java/org/hibernate/id/uuid/UuidGenerator.java

@@ -21,7 +21,7 @@ import static org.hibernate.annotations.UuidGenerator.Style.TIME;
 import static org.hibernate.internal.util.ReflectHelper.getPropertyType;
 
 /**
- * UUID-based IdentifierGenerator
+ * Generates {@link UUID}s.
  *
  * @see org.hibernate.annotations.UuidGenerator
  */

hibernate-core/src/main/java/org/hibernate/tuple/CreationTimestampGeneration.java

@@ -6,17 +6,21 @@
  */
 package org.hibernate.tuple;
 
+import org.hibernate.Internal;
+import org.hibernate.Remove;
 import org.hibernate.annotations.CreationTimestamp;
 import org.hibernate.annotations.SourceType;
 import org.hibernate.dialect.Dialect;
 
 /**
- * Value generation implementation for {@link CreationTimestamp}.
+ * Value generation implementation for {@link CreationTimestamp}, no longer used.
  *
  * @author Gunnar Morling
  *
- * @see org.hibernate.annotations.CurrentTimestampGeneration
+ * @deprecated use {@link CurrentTimestampGeneration}
  */
+@Internal
+@Deprecated(since = "6.2") @Remove
 public class CreationTimestampGeneration implements AnnotationValueGeneration<CreationTimestamp> {
 
 	private ValueGenerator<?> generator;

hibernate-core/src/main/java/org/hibernate/tuple/CurrentTimestampGeneration.java

@@ -0,0 +1,96 @@
+/*
+ * 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.tuple;
+
+import org.hibernate.AssertionFailure;
+import org.hibernate.Internal;
+import org.hibernate.annotations.CreationTimestamp;
+import org.hibernate.annotations.CurrentTimestamp;
+import org.hibernate.annotations.SourceType;
+import org.hibernate.annotations.UpdateTimestamp;
+import org.hibernate.dialect.Dialect;
+import org.hibernate.internal.util.ReflectHelper;
+
+import java.lang.reflect.Member;
+
+import static org.hibernate.tuple.GenerationTiming.ALWAYS;
+import static org.hibernate.tuple.GenerationTiming.INSERT;
+
+/**
+ * Value generation strategy which produces a timestamp using the database
+ * {@link Dialect#currentTimestamp() current_timestamp} function or the JVM
+ * {@linkplain java.time.Clock#instant() current instant}.
+ * <p>
+ * Underlies the {@link CurrentTimestamp}, {@link CreationTimestamp}, and
+ * {@link UpdateTimestamp} annotations.
+ *
+ * @see CurrentTimestamp
+ * @see CreationTimestamp
+ * @see UpdateTimestamp
+ *
+ * @since 6.0
+ *
+ * @author Steve Ebersole
+ * @author Gavin King
+ */
+@Internal
+public class CurrentTimestampGeneration implements ValueGeneration {
+	private final GenerationTiming timing;
+	private final ValueGenerator<?> generator;
+
+	public CurrentTimestampGeneration(CurrentTimestamp annotation, Member member, GeneratorCreationContext context) {
+		generator = getGenerator( annotation.source(), member );
+		timing = annotation.timing();
+	}
+
+	public CurrentTimestampGeneration(CreationTimestamp annotation, Member member, GeneratorCreationContext context) {
+		generator = getGenerator( annotation.source(), member );
+		timing = INSERT;
+	}
+
+	public CurrentTimestampGeneration(UpdateTimestamp annotation, Member member, GeneratorCreationContext context) {
+		generator = getGenerator( annotation.source(), member );
+		timing = ALWAYS;
+	}
+
+	private static ValueGenerator<?> getGenerator(SourceType source, Member member) {
+		switch (source) {
+			case VM:
+				// ValueGenerator is only used for in-VM generation
+				return TimestampGenerators.get( ReflectHelper.getPropertyType( member ) );
+			case DB:
+				return null;
+			default:
+				throw new AssertionFailure("unknown source");
+		}
+	}
+
+	@Override
+	public GenerationTiming getGenerationTiming() {
+		return timing;
+	}
+
+	@Override
+	public ValueGenerator<?> getValueGenerator() {
+		return generator;
+	}
+
+	@Override
+	public boolean referenceColumnInSql() {
+		return true;
+	}
+
+	@Override
+	public String getDatabaseGeneratedReferencedColumnValue() {
+		return "current_timestamp";
+	}
+
+	@Override
+	public String getDatabaseGeneratedReferencedColumnValue(Dialect dialect) {
+		return dialect.currentTimestamp();
+	}
+}

hibernate-core/src/main/java/org/hibernate/tuple/SourceGeneration.java

@@ -4,20 +4,16 @@
  * 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.annotations;
+package org.hibernate.tuple;
 
 import org.hibernate.AssertionFailure;
 import org.hibernate.Internal;
 import org.hibernate.Session;
+import org.hibernate.annotations.Source;
 import org.hibernate.dialect.Dialect;
 import org.hibernate.engine.jdbc.spi.JdbcCoordinator;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.internal.CoreMessageLogger;
-import org.hibernate.tuple.GenerationTiming;
-import org.hibernate.tuple.GeneratorCreationContext;
-import org.hibernate.tuple.InMemoryGenerator;
-import org.hibernate.tuple.TimestampGenerators;
-import org.hibernate.tuple.ValueGenerator;
 import org.jboss.logging.Logger;
 
 import java.lang.reflect.Member;
@@ -40,12 +36,11 @@ import static org.hibernate.tuple.GenerationTiming.ALWAYS;
  *
  * @author Gavin King
  *
- * @deprecated because {@link Source} is generated, though this implementation is instructive
+ * @deprecated because {@link Source} is deprecated, though this implementation is instructive
  */
 @Deprecated(since = "6.2")
 @Internal
-public class SourceGeneration
+public class SourceGeneration implements InMemoryGenerator, ValueGenerator<Object> {
-		implements InMemoryGenerator, ValueGenerator<Object> {
 
 	private static final CoreMessageLogger log = Logger.getMessageLogger(
 			CoreMessageLogger.class,

hibernate-core/src/main/java/org/hibernate/tuple/UpdateTimestampGeneration.java

@@ -6,17 +6,21 @@
  */
 package org.hibernate.tuple;
 
+import org.hibernate.Internal;
+import org.hibernate.Remove;
 import org.hibernate.annotations.SourceType;
 import org.hibernate.annotations.UpdateTimestamp;
 import org.hibernate.dialect.Dialect;
 
 /**
- * Value generation implementation for {@link UpdateTimestamp}.
+ * Value generation implementation for {@link UpdateTimestamp}, no longer used.
  *
  * @author Gunnar Morling
  *
- * @see org.hibernate.annotations.CurrentTimestampGeneration
+ * @deprecated use {@link CurrentTimestampGeneration}
  */
+@Internal
+@Deprecated(since = "6.2") @Remove
 public class UpdateTimestampGeneration implements AnnotationValueGeneration<UpdateTimestamp> {
 
 	private ValueGenerator<?> generator;

hibernate-core/src/main/java/org/hibernate/tuple/VmValueGeneration.java

@@ -9,6 +9,7 @@ package org.hibernate.tuple;
 import java.lang.reflect.Constructor;
 
 import org.hibernate.HibernateException;
+import org.hibernate.Internal;
 import org.hibernate.Session;
 import org.hibernate.annotations.GeneratorType;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
@@ -17,11 +18,15 @@ import static org.hibernate.internal.util.ReflectHelper.getDefaultConstructor;
 
 /**
  * An {@link AnnotationValueGeneration} which delegates to a {@link ValueGenerator}.
+ * Underlies the {@link GeneratorType} annotation.
  *
  * @author Gunnar Morling
+ *
+ * @deprecated since {@link GeneratorType} is deprecated
  */
-public class VmValueGeneration
+@Internal
-		implements InMemoryGenerator {
+@Deprecated(since = "6.2")
+public class VmValueGeneration implements InMemoryGenerator {
 
 	private final GenerationTiming generationTiming;
 	private final ValueGenerator<?> generator;