HHH-18829 Hibernate Processor - representing gnerated ID class as member of parent AnnotationMetaEntity

Author: cigaly

tooling/metamodel-generator/src/main/java/org/hibernate/processor/ClassWriter.java

@@ -6,7 +6,6 @@
 
 import org.hibernate.processor.model.MetaAttribute;
 import org.hibernate.processor.model.Metamodel;
-import org.hibernate.processor.util.Constants;
 
 import javax.annotation.processing.FilerException;
 import javax.lang.model.element.ElementKind;
@@ -21,9 +20,6 @@
 import java.time.format.DateTimeFormatter;
 import java.util.List;
 
-import static org.hibernate.processor.util.TypeUtils.hasAnnotation;
-import static org.hibernate.processor.util.TypeUtils.isAnnotationMirrorOfType;
-
 /**
  * Helper class to write the actual metamodel class using the  {@link javax.annotation.processing.Filer} API.
  *
@@ -104,8 +100,6 @@ private static StringBuffer generateBody(Metamodel entity, Context context) {
 
 			pw.println();
 
-			generateIdClassIfNeeded( entity, pw );
-
 			final List<MetaAttribute> members = entity.getMembers();
 			for ( MetaAttribute metaMember : members ) {
 				if ( metaMember.hasStringAttribute() ) {
@@ -236,23 +230,4 @@ private static String writeStaticMetaModelAnnotation(Metamodel entity) {
 		return "@" + entity.importType( annotation ) + "(" + entity.getSimpleName() + ".class)";
 	}
 
-	private static void generateIdClassIfNeeded(Metamodel entity, PrintWriter pw) {
-		if ( hasAnnotation( entity.getElement(), Constants.ID_CLASS ) ) {
-			return;
-		}
-
-		final List<String> idFields = entity.getMembers().stream()
-				.filter( a -> a.inheritedAnnotations().stream()
-						.anyMatch( m -> isAnnotationMirrorOfType( m, Constants.ID ) )
-				)
-				.map( a -> entity.importType( a.getTypeDeclaration() ) + " " + a.getPropertyName() )
-				.toList();
-
-		if ( idFields.size() > 1 ) {
-			pw.print( "public record Id(" );
-			pw.print( String.join( ", ", idFields ) );
-			pw.println( ") {}" );
-			pw.println();
-		}
-	}
 }

tooling/metamodel-generator/src/main/java/org/hibernate/processor/annotation/AnnotationMetaEntity.java

@@ -53,7 +53,6 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
-import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -108,6 +107,8 @@
  */
 public class AnnotationMetaEntity extends AnnotationMeta {
 
+	private static final String ID_CLASS_MEMBER_NAME = "<ID_CLASS>";
+
 	private final ImportContext importContext;
 	private final TypeElement element;
 	private final Map<String, MetaAttribute> members;
@@ -168,7 +169,7 @@ public AnnotationMetaEntity(
 		this.element = element;
 		this.context = context;
 		this.managed = managed;
-		this.members = new LinkedHashMap<>();	// Order should be preserved!
+		this.members = new HashMap<>();
 		this.quarkusInjection = context.isQuarkusInjection();
 		this.importContext = new ImportContextImpl( getPackageName( context, element ) );
 		jakartaDataStaticModel = jakartaDataStaticMetamodel;
@@ -440,6 +441,8 @@ && containsAnnotation( method, HQL, SQL, FIND ) ) {
 
 			addPersistentMembers( fieldsOfClass, AccessType.FIELD );
 			addPersistentMembers( gettersAndSettersOfClass, AccessType.PROPERTY );
+
+			addIdClassIfNeeded( fieldsOfClass, gettersAndSettersOfClass );
 		}
 
 		addAuxiliaryMembers();
@@ -453,6 +456,33 @@ && containsAnnotation( method, HQL, SQL, FIND ) ) {
 		initialized = true;
 	}
 
+	private void addIdClassIfNeeded(List<? extends Element> fields, List<? extends Element> methods) {
+		if ( hasAnnotation( element, ID_CLASS ) ) {
+			return;
+		}
+		final List<MetaAttribute> components = new ArrayList<>();
+		for ( Element field : fields ) {
+			if ( hasAnnotation( field, ID ) && isPersistent( field, AccessType.FIELD ) ) {
+				final String propertyName = propertyName( this, field );
+				if ( members.containsKey( propertyName ) ) {
+					components.add( members.get( propertyName ) );
+				}
+			}
+		}
+		for ( Element method : methods ) {
+			if ( hasAnnotation( method, ID ) && isPersistent( method, AccessType.PROPERTY ) ) {
+				final String propertyName = propertyName( this, method );
+				if ( members.containsKey( propertyName ) ) {
+					components.add( members.get( propertyName ) );
+				}
+			}
+		}
+		if ( components.size() < 2 ) {
+			return;
+		}
+		putMember( ID_CLASS_MEMBER_NAME, new IdClassMetaAttribute( this, components ) );
+	}
+
 	private boolean checkEntities(List<ExecutableElement> lifecycleMethods) {
 		boolean foundPersistenceEntity = false;
 		VariableElement nonPersistenceParameter = null;

tooling/metamodel-generator/src/main/java/org/hibernate/processor/annotation/IdClassMetaAttribute.java

@@ -0,0 +1,73 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.processor.annotation;
+
+import org.hibernate.processor.model.MetaAttribute;
+import org.hibernate.processor.model.Metamodel;
+
+import java.util.List;
+
+public class IdClassMetaAttribute implements MetaAttribute {
+
+	private final Metamodel parent;
+
+	private final List<MetaAttribute> components;
+
+	public IdClassMetaAttribute(Metamodel parent, List<MetaAttribute> components) {
+		this.parent = parent;
+		this.components = components;
+	}
+
+	@Override
+	public boolean hasTypedAttribute() {
+		return true;
+	}
+
+	@Override
+	public boolean hasStringAttribute() {
+		return false;
+	}
+
+	@Override
+	public String getAttributeDeclarationString() {
+		final StringBuilder decl = new StringBuilder()
+				.append("\n/**\n * Static ID class for {@link ")
+				.append( parent.getQualifiedName() )
+				.append( "}\n **/\n" )
+				.append( "public record Id" );
+		String delimiter = "(";
+		for ( MetaAttribute component : components ) {
+			decl.append( delimiter ).append( parent.importType( component.getTypeDeclaration() ) )
+					.append( ' ' ).append( component.getPropertyName() );
+			delimiter = ", ";
+		}
+		return decl.append( ") {}" ).toString();
+	}
+
+	@Override
+	public String getAttributeNameDeclarationString() {
+		return "";
+	}
+
+	@Override
+	public String getMetaType() {
+		return "";
+	}
+
+	@Override
+	public String getPropertyName() {
+		return "";
+	}
+
+	@Override
+	public String getTypeDeclaration() {
+		return "";
+	}
+
+	@Override
+	public Metamodel getHostingEntity() {
+		return parent;
+	}
+}