HHH-4396 - Ability to patternize embedded column names

Author: sebersole

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

@@ -4,6 +4,8 @@
  */
 package org.hibernate.annotations;
 
+import org.hibernate.Incubating;
+
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
@@ -18,10 +20,12 @@
  * {@code @Embedded @EmbeddedColumnNaming("home_%s)}, we will get columns named
  * {@code home_street}, {@code home_city}, etc.
  *
+ * @since 7.0
  * @author Steve Ebersole
  */
 @Target({METHOD, FIELD})
 @Retention(RUNTIME)
+@Incubating
 public @interface EmbeddedColumnNaming {
 	/**
 	 * The naming pattern.  It is expected to contain a single pattern marker ({@code %})

hibernate-core/src/main/java/org/hibernate/boot/models/HibernateAnnotations.java

@@ -240,6 +240,10 @@ public interface HibernateAnnotations {
 			EmbeddableInstantiatorRegistrationAnnotation.class,
 			EMBEDDABLE_INSTANTIATOR_REGISTRATIONS
 	);
+	OrmAnnotationDescriptor<EmbeddedColumnNaming,EmbeddedColumnNamingAnnotation> EMBEDDED_COLUMN_NAMING = new OrmAnnotationDescriptor<>(
+			EmbeddedColumnNaming.class,
+			EmbeddedColumnNamingAnnotation.class
+	);
 	OrmAnnotationDescriptor<Fetch,FetchAnnotation> FETCH = new OrmAnnotationDescriptor<>(
 			Fetch.class,
 			FetchAnnotation.class

hibernate-core/src/main/java/org/hibernate/boot/models/annotations/internal/EmbeddedColumnNamingAnnotation.java

@@ -0,0 +1,54 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.boot.models.annotations.internal;
+
+import org.hibernate.annotations.EmbeddedColumnNaming;
+import org.hibernate.models.spi.SourceModelBuildingContext;
+
+import java.lang.annotation.Annotation;
+import java.util.Map;
+
+@SuppressWarnings({ "ClassExplicitlyAnnotation", "unused" })
+public class EmbeddedColumnNamingAnnotation implements EmbeddedColumnNaming {
+	private String value;
+
+	/**
+	 * Used in creating dynamic annotation instances (e.g. from XML)
+	 */
+	public EmbeddedColumnNamingAnnotation(SourceModelBuildingContext modelContext) {
+	}
+
+	/**
+	 * Used in creating annotation instances from JDK variant
+	 */
+	public EmbeddedColumnNamingAnnotation(
+			EmbeddedColumnNaming annotation,
+			SourceModelBuildingContext modelContext) {
+		this.value = annotation.value();
+	}
+
+	/**
+	 * Used in creating annotation instances from Jandex variant
+	 */
+	public EmbeddedColumnNamingAnnotation(
+			Map<String, Object> attributeValues,
+			SourceModelBuildingContext modelContext) {
+		this.value = (String) attributeValues.get( "value" );
+	}
+
+	@Override
+	public Class<? extends Annotation> annotationType() {
+		return EmbeddedColumnNaming.class;
+	}
+
+	@Override
+	public String value() {
+		return value;
+	}
+
+	public void value(String value) {
+		this.value = value;
+	}
+}

migration-guide.adoc

@@ -132,6 +132,44 @@ in addition to the previous truth-based strategies.
 See the link:{user-guide-url}#soft-delete[User Guide] for details.
 
 
+[[embedded-column-naming]]
+== @EmbeddedColumnNaming
+
+A long requested feature for both Hibernate and Jakarta Persistence has been the ability to
+define a prefix for the names of columns associated with an embedded value.
+
+7.0 adds support for this using the new `@EmbeddedColumnNaming` annotation.  The annotation
+accepts a format pattern, so is a little more flexible than just a prefix.
+
+Consider a typical Person / Address composition:
+
+[source,java]
+----
+@Embeddable
+class Address {
+    String street;
+	String city;
+	...
+}
+
+@Entity
+class Person {
+	...
+
+    @Embedded
+    @EmbeddedColumnNaming("home_%")
+    Address homeAddress;
+
+    @Embedded
+    @EmbeddedColumnNaming("work_%")
+    Address workAddress;
+
+}
+----
+
+This triggers Hibernate to use the column names `home_street`, `home_city`, `work_street`, ...
+
+
 [[envers-rev-types]]
 == Hibernate Envers and custom revision entities