/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2011, Red Hat Inc. or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.metamodel.source.annotations;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.persistence.AccessType;
import org.hibernate.AnnotationException;
import org.hibernate.internal.util.collections.CollectionHelper;
import org.hibernate.metamodel.binding.InheritanceType;
import org.hibernate.metamodel.source.annotations.entity.EntityClass;
import org.hibernate.metamodel.source.annotations.entity.RootEntitySourceImpl;
import org.hibernate.metamodel.source.annotations.entity.SubclassEntitySourceImpl;
import org.hibernate.metamodel.source.binder.EntityHierarchy;
import org.hibernate.metamodel.source.binder.EntitySource;
import org.hibernate.metamodel.source.binder.SubclassEntitySource;
import org.jboss.jandex.AnnotationInstance;
import org.jboss.jandex.ClassInfo;
import org.jboss.jandex.DotName;
import org.jboss.jandex.FieldInfo;
import org.jboss.jandex.Index;
import org.jboss.jandex.MethodInfo;
/**
* Given a (jandex) annotation index build processes all classes with JPA relevant annotations and pre-orders
* JPA entities respectively their inheritance hierarchy.
*
* @author Hardy Ferentschik
*/
public class EntityHierarchyBuilder {
private static final DotName OBJECT = DotName.createSimple( Object.class.getName() );
/**
* Pre-processes the annotated entities from the index and create a set of entity hierarchies which can be bound
* to the metamodel.
*
* @param bindingContext The binding context, giving access to needed services and information
*
* @return a set of {@code EntityHierarchy} instances.
*/
public static Set<EntityHierarchy> createEntityHierarchies(AnnotationBindingContext bindingContext) {
Set<EntityHierarchy> hierarchies = new HashSet<EntityHierarchy>();
List<DotName> processedEntities = new ArrayList<DotName>();
Map<DotName, List<ClassInfo>> classToDirectSubClassMap = new HashMap<DotName, List<ClassInfo>>();
Index index = bindingContext.getIndex();
for ( ClassInfo info : index.getKnownClasses() ) {
if ( !isEntityClass( info ) ) {
continue;
}
if ( processedEntities.contains( info.name() ) ) {
continue;
}
ClassInfo rootClassInfo = findRootEntityClassInfo( index, info );
List<ClassInfo> rootClassWithAllSubclasses = new ArrayList<ClassInfo>();
// the root entity might have some mapped super classes which we have to take into consideration
// for inheritance type and default access
addMappedSuperclasses( index, rootClassInfo, rootClassWithAllSubclasses );
// collect the current root entity and all its subclasses
processHierarchy(
bindingContext,
rootClassInfo,
rootClassWithAllSubclasses,
processedEntities,
classToDirectSubClassMap
);
AccessType defaultAccessType = determineDefaultAccessType( rootClassWithAllSubclasses );
InheritanceType hierarchyInheritanceType = determineInheritanceType(
rootClassInfo,
rootClassWithAllSubclasses
);
// create the root entity source
EntityClass rootEntityClass = new EntityClass(
rootClassInfo,
null,
defaultAccessType,
hierarchyInheritanceType,
bindingContext
);
RootEntitySourceImpl rootSource = new RootEntitySourceImpl( rootEntityClass );
addSubclassEntitySources(
bindingContext,
classToDirectSubClassMap,
defaultAccessType,
hierarchyInheritanceType,
rootEntityClass,
rootSource
);
hierarchies.add( new EntityHierarchyImpl( rootSource, hierarchyInheritanceType ) );
}
return hierarchies;
}
private static void addSubclassEntitySources(AnnotationBindingContext bindingContext,
Map<DotName, List<ClassInfo>> classToDirectSubClassMap,
AccessType defaultAccessType,
InheritanceType hierarchyInheritanceType,
EntityClass entityClass,
EntitySource entitySource) {
List<ClassInfo> subClassInfoList = classToDirectSubClassMap.get( DotName.createSimple( entitySource.getClassName() ) );
if ( subClassInfoList == null ) {
return;
}
for ( ClassInfo subClassInfo : subClassInfoList ) {
EntityClass subclassEntityClass = new EntityClass(
subClassInfo,
entityClass,
defaultAccessType,
hierarchyInheritanceType,
bindingContext
);
SubclassEntitySource subclassEntitySource = new SubclassEntitySourceImpl( subclassEntityClass );
entitySource.add( subclassEntitySource );
addSubclassEntitySources(
bindingContext,
classToDirectSubClassMap,
defaultAccessType,
hierarchyInheritanceType,
subclassEntityClass,
subclassEntitySource
);
}
}
/**
* Finds the root entity starting at the entity given by {@code info}. The root entity is not the highest superclass
* in a java type sense, but the highest superclass which is also an entity (annotated w/ {@code @Entity}.
*
* @param index the annotation repository
* @param info the class info representing an entity
*
* @return Finds the root entity starting at the entity given by {@code info}
*/
private static ClassInfo findRootEntityClassInfo(Index index, ClassInfo info) {
ClassInfo rootEntity = info;
DotName superName = info.superName();
ClassInfo tmpInfo;
// walk up the hierarchy until java.lang.Object
while ( !OBJECT.equals( superName ) ) {
tmpInfo = index.getClassByName( superName );
if ( isEntityClass( tmpInfo ) ) {
rootEntity = tmpInfo;
}
superName = tmpInfo.superName();
}
return rootEntity;
}
private static void addMappedSuperclasses(Index index, ClassInfo info, List<ClassInfo> classInfoList) {
DotName superName = info.superName();
ClassInfo tmpInfo;
// walk up the hierarchy until java.lang.Object
while ( !OBJECT.equals( superName ) ) {
tmpInfo = index.getClassByName( superName );
if ( isMappedSuperclass( tmpInfo ) ) {
classInfoList.add( tmpInfo );
}
superName = tmpInfo.superName();
}
}
/**
* This method does several things.
* <ul>
* <li>Collect all java subclasses (recursive) of {@code classInfo} in {@code rootClassWithAllSubclasses}. </li>
* <li>Keeping track of all processed classed annotated with {@code @Entity}</li>
* <li>Building up a map of class to direct subclass list</li>
* </ul>
*
* @param bindingContext the binding context
* @param classInfo the current class info
* @param rootClassWithAllSubclasses used to collect all classes in the hierarchy starting at {@code classInfo}
* @param processedEntities Used to keep track of all processed entities
* @param classToDirectSubclassMap Create a map of class to direct subclass
*/
private static void processHierarchy(AnnotationBindingContext bindingContext,
ClassInfo classInfo,
List<ClassInfo> rootClassWithAllSubclasses,
List<DotName> processedEntities,
Map<DotName, List<ClassInfo>> classToDirectSubclassMap) {
processedEntities.add( classInfo.name() );
rootClassWithAllSubclasses.add( classInfo );
List<ClassInfo> subClasses = bindingContext.getIndex().getKnownDirectSubclasses( classInfo.name() );
// if there are no more subclasses we reached the leaf class. In order to properly resolve generics we
// need to resolve the type information using this leaf class
if ( subClasses.isEmpty() ) {
bindingContext.resolveAllTypes( classInfo.name().toString() );
}
for ( ClassInfo subClassInfo : subClasses ) {
addSubClassToSubclassMap( classInfo.name(), subClassInfo, classToDirectSubclassMap );
processHierarchy(
bindingContext,
subClassInfo,
rootClassWithAllSubclasses,
processedEntities,
classToDirectSubclassMap
);
}
}
private static void addSubClassToSubclassMap(DotName name, ClassInfo subClassInfo, Map<DotName, List<ClassInfo>> classToDirectSubclassMap) {
if ( classToDirectSubclassMap.containsKey( name ) ) {
classToDirectSubclassMap.get( name ).add( subClassInfo );
}
else {
List<ClassInfo> subclassList = new ArrayList<ClassInfo>();
subclassList.add( subClassInfo );
classToDirectSubclassMap.put( name, subclassList );
}
}
/**
* Checks whether the class info represents an entity.
*
* @param info the jandex class info
*
* @return {@code true} if the class represented by {@code info} is annotated with {@code @Entity}, {@code false} otherwise.
*/
private static boolean isEntityClass(ClassInfo info) {
if ( info == null ) {
return false;
}
// we are only interested in building the class hierarchies for @Entity
AnnotationInstance jpaEntityAnnotation = JandexHelper.getSingleAnnotation( info, JPADotNames.ENTITY );
if ( jpaEntityAnnotation == null ) {
return false;
}
// some sanity checks
AnnotationInstance mappedSuperClassAnnotation = JandexHelper.getSingleAnnotation(
info, JPADotNames.MAPPED_SUPERCLASS
);
String className = info.toString();
assertNotEntityAndMappedSuperClass( jpaEntityAnnotation, mappedSuperClassAnnotation, className );
AnnotationInstance embeddableAnnotation = JandexHelper.getSingleAnnotation(
info, JPADotNames.EMBEDDABLE
);
assertNotEntityAndEmbeddable( jpaEntityAnnotation, embeddableAnnotation, className );
return true;
}
/**
* Checks whether the class info represents a mapped superclass.
*
* @param info the jandex class info
*
* @return {@code true} if the class represented by {@code info} is annotated with {@code @MappedSuperclass}, {@code false} otherwise.
*/
private static boolean isMappedSuperclass(ClassInfo info) {
if ( info == null ) {
return false;
}
// we are only interested in building the class hierarchies for @Entity
AnnotationInstance mappedSuperclassAnnotation = JandexHelper.getSingleAnnotation(
info,
JPADotNames.MAPPED_SUPERCLASS
);
return mappedSuperclassAnnotation != null;
}
private static void assertNotEntityAndMappedSuperClass(AnnotationInstance jpaEntityAnnotation, AnnotationInstance mappedSuperClassAnnotation, String className) {
if ( jpaEntityAnnotation != null && mappedSuperClassAnnotation != null ) {
throw new AnnotationException(
"An entity cannot be annotated with both @Entity and @MappedSuperclass. " + className + " has both annotations."
);
}
}
private static void assertNotEntityAndEmbeddable(AnnotationInstance jpaEntityAnnotation, AnnotationInstance embeddableAnnotation, String className) {
if ( jpaEntityAnnotation != null && embeddableAnnotation != null ) {
throw new AnnotationException(
"An entity cannot be annotated with both @Entity and @Embeddable. " + className + " has both annotations."
);
}
}
/**
* @param classes the classes in the hierarchy
*
* @return Returns the default access type for the configured class hierarchy independent of explicit
* {@code AccessType} annotations. The default access type is determined by the placement of the
* annotations.
*/
private static AccessType determineDefaultAccessType(List<ClassInfo> classes) {
AccessType accessTypeByEmbeddedIdPlacement = null;
AccessType accessTypeByIdPlacement = null;
for ( ClassInfo info : classes ) {
List<AnnotationInstance> idAnnotations = info.annotations().get( JPADotNames.ID );
List<AnnotationInstance> embeddedIdAnnotations = info.annotations().get( JPADotNames.EMBEDDED_ID );
if ( CollectionHelper.isNotEmpty( embeddedIdAnnotations ) ) {
accessTypeByEmbeddedIdPlacement = determineAccessTypeByIdPlacement( embeddedIdAnnotations );
}
if ( CollectionHelper.isNotEmpty( idAnnotations ) ) {
accessTypeByIdPlacement = determineAccessTypeByIdPlacement( idAnnotations );
}
}
if ( accessTypeByEmbeddedIdPlacement != null ) {
return accessTypeByEmbeddedIdPlacement;
}
else if ( accessTypeByIdPlacement != null ) {
return accessTypeByIdPlacement;
}
else {
return throwIdNotFoundAnnotationException( classes );
}
}
private static AccessType determineAccessTypeByIdPlacement(List<AnnotationInstance> idAnnotations) {
AccessType accessType = null;
for ( AnnotationInstance annotation : idAnnotations ) {
AccessType tmpAccessType;
if ( annotation.target() instanceof FieldInfo ) {
tmpAccessType = AccessType.FIELD;
}
else if ( annotation.target() instanceof MethodInfo ) {
tmpAccessType = AccessType.PROPERTY;
}
else {
throw new AnnotationException( "Invalid placement of @Id annotation" );
}
if ( accessType == null ) {
accessType = tmpAccessType;
}
else {
if ( !accessType.equals( tmpAccessType ) ) {
throw new AnnotationException( "Inconsistent placement of @Id annotation within hierarchy " );
}
}
}
return accessType;
}
private static InheritanceType determineInheritanceType(ClassInfo rootClassInfo, List<ClassInfo> classes) {
if(classes.size() == 1) {
return InheritanceType.NO_INHERITANCE;
}
// if we have more than one entity class the default is SINGLE_TABLE
InheritanceType inheritanceType = InheritanceType.SINGLE_TABLE;
AnnotationInstance inheritanceAnnotation = JandexHelper.getSingleAnnotation(
rootClassInfo, JPADotNames.INHERITANCE
);
if ( inheritanceAnnotation != null ) {
String enumName = inheritanceAnnotation.value( "strategy" ).asEnum();
javax.persistence.InheritanceType jpaInheritanceType = Enum.valueOf(
javax.persistence.InheritanceType.class, enumName
);
inheritanceType = InheritanceType.get( jpaInheritanceType );
}
// sanity check that the is no other @Inheritance annotation in the hierarchy
for ( ClassInfo info : classes ) {
if ( rootClassInfo.equals( info ) ) {
continue;
}
inheritanceAnnotation = JandexHelper.getSingleAnnotation(
info, JPADotNames.INHERITANCE
);
if ( inheritanceAnnotation != null ) {
throw new AnnotationException(
String.format(
"The inheritance type for %s must be specified on the root entity %s",
hierarchyListString( classes ),
rootClassInfo.name().toString()
)
);
}
}
return inheritanceType;
}
private static AccessType throwIdNotFoundAnnotationException(List<ClassInfo> classes) {
StringBuilder builder = new StringBuilder();
builder.append( "Unable to determine identifier attribute for class hierarchy consisting of the classe(s) " );
builder.append( hierarchyListString( classes ) );
throw new AnnotationException( builder.toString() );
}
private static String hierarchyListString(List<ClassInfo> classes) {
StringBuilder builder = new StringBuilder();
builder.append( "[" );
int count = 0;
for ( ClassInfo info : classes ) {
builder.append( info.name().toString() );
if ( count < classes.size() - 1 ) {
builder.append( ", " );
}
count++;
}
builder.append( "]" );
return builder.toString();
}
}