/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2009 by Red Hat Inc and/or its affiliates or by
* third-party contributors as indicated by either @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.jpa.criteria.path;
import java.io.Serializable;
import java.lang.reflect.Member;
import java.util.Map;
import javax.persistence.criteria.Join;
import javax.persistence.criteria.MapJoin;
import javax.persistence.criteria.Path;
import javax.persistence.metamodel.Attribute;
import javax.persistence.metamodel.Bindable;
import javax.persistence.metamodel.ManagedType;
import javax.persistence.metamodel.MapAttribute;
import javax.persistence.metamodel.SingularAttribute;
import javax.persistence.metamodel.Type;
import org.hibernate.jpa.criteria.compile.RenderingContext;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.jpa.criteria.CriteriaBuilderImpl;
import org.hibernate.jpa.criteria.PathSource;
import org.hibernate.jpa.criteria.MapJoinImplementor;
import org.hibernate.jpa.criteria.PathImplementor;
import org.hibernate.persister.collection.CollectionPersister;
/**
* {@link MapJoin#key} poses a number of implementation difficulties in terms of the type signatures
* amongst the {@link Path}, {@link Join} and {@link Attribute} reference at play. The implementations found here
* provide that bridge.
*
* @author Steve Ebersole
*/
public class MapKeyHelpers {
/**
* Models a path to a map key. This is the actual return used from {@link MapJoin#key}
*
* @param <K> The type of the map key.
*/
public static class MapKeyPath<K>
extends AbstractPathImpl<K>
implements PathImplementor<K>, Serializable {
private final MapKeyAttribute<K> mapKeyAttribute;
public MapKeyPath(
CriteriaBuilderImpl criteriaBuilder,
MapKeySource<K,?> source,
MapKeyAttribute<K> mapKeyAttribute) {
super( criteriaBuilder, mapKeyAttribute.getJavaType(), source );
this.mapKeyAttribute = mapKeyAttribute;
}
@Override
public MapKeySource getPathSource() {
return (MapKeySource) super.getPathSource();
}
public MapKeyAttribute<K> getAttribute() {
return mapKeyAttribute;
}
private boolean isBasicTypeKey() {
return Attribute.PersistentAttributeType.BASIC ==
mapKeyAttribute.getPersistentAttributeType();
}
@Override
protected boolean canBeDereferenced() {
return ! isBasicTypeKey();
}
@Override
protected Attribute locateAttributeInternal(String attributeName) {
if ( ! canBeDereferenced() ) {
throw new IllegalArgumentException(
"Map key [" + getPathSource().getPathIdentifier() + "] cannot be dereferenced"
);
}
throw new UnsupportedOperationException( "Not yet supported!" );
}
public Bindable<K> getModel() {
return mapKeyAttribute;
}
@Override
@SuppressWarnings("unchecked")
public <T extends K> MapKeyPath<T> treatAs(Class<T> treatAsType) {
// todo : if key is an entity, this is probably not enough
return (MapKeyPath<T>) this;
}
@Override
public String render(RenderingContext renderingContext) {
PathSource<?> source = getPathSource();
String name;
if ( source != null ) {
source.prepareAlias( renderingContext );
name = source.getPathIdentifier();
}
else {
name = getAttribute().getName();
}
return "key(" + name + ")";
}
}
/**
* Defines a {@link Path} for the map which can then be used to represent the source of the
* map key "attribute".
*
* @param <K> The map key type
* @param <V> The map value type
*/
public static class MapKeySource<K,V>
extends AbstractPathImpl<Map<K, V>>
implements PathImplementor<Map<K, V>>, Serializable {
private final MapAttribute<?,K,V> mapAttribute;
private final MapJoinImplementor<?,K,V> mapJoin;
public MapKeySource(
CriteriaBuilderImpl criteriaBuilder,
Class<Map<K, V>> javaType,
MapJoinImplementor<?,K,V> mapJoin,
MapAttribute<?,K,V> attribute) {
super( criteriaBuilder, javaType, null );
this.mapJoin = mapJoin;
this.mapAttribute = attribute;
}
public MapAttribute<?,K,V> getAttribute() {
return mapAttribute;
}
@SuppressWarnings({ "unchecked" })
public Bindable<Map<K, V>> getModel() {
// TODO : ok??? the attribute is in fact bindable, but its type signature is different
return (Bindable<Map<K, V>>) mapAttribute;
}
@Override
public PathImplementor<?> getParentPath() {
return (PathImplementor<?>) mapJoin.getParentPath();
}
@Override
protected boolean canBeDereferenced() {
return false;
}
@Override
protected Attribute locateAttributeInternal(String attributeName) {
throw new IllegalArgumentException( "Map [" + mapJoin.getPathIdentifier() + "] cannot be dereferenced" );
}
@Override
public <T extends Map<K, V>> PathImplementor<T> treatAs(Class<T> treatAsType) {
throw new UnsupportedOperationException();
}
@Override
public String getPathIdentifier() {
return mapJoin.getPathIdentifier();
}
}
/**
* Disallow instantiation
*/
private MapKeyHelpers() {
}
/**
* Defines an {@link javax.persistence.metamodel.Attribute} modelling of a map-key.
*
* @param <K> The type of the map key
*/
public static class MapKeyAttribute<K>
implements SingularAttribute<Map<K,?>,K>, Bindable<K>, Serializable {
private final MapAttribute<?,K,?> attribute;
private final CollectionPersister mapPersister;
private final org.hibernate.type.Type mapKeyType;
private final Type<K> jpaType;
private final BindableType jpaBindableType;
private final Class<K> jpaBinableJavaType;
private final PersistentAttributeType persistentAttributeType;
public MapKeyAttribute(CriteriaBuilderImpl criteriaBuilder, MapAttribute<?, K, ?> attribute) {
this.attribute = attribute;
this.jpaType = attribute.getKeyType();
this.jpaBinableJavaType = attribute.getKeyJavaType();
this.jpaBindableType = Type.PersistenceType
.ENTITY.equals( jpaType.getPersistenceType() )
? BindableType.ENTITY_TYPE
: BindableType.SINGULAR_ATTRIBUTE;
String guessedRoleName = determineRole( attribute );
SessionFactoryImplementor sfi = criteriaBuilder.getEntityManagerFactory().getSessionFactory();
mapPersister = sfi.getCollectionPersister( guessedRoleName );
if ( mapPersister == null ) {
throw new IllegalStateException( "Could not locate collection persister [" + guessedRoleName + "]" );
}
mapKeyType = mapPersister.getIndexType();
if ( mapKeyType == null ) {
throw new IllegalStateException( "Could not determine map-key type [" + guessedRoleName + "]" );
}
this.persistentAttributeType = mapKeyType.isEntityType()
? PersistentAttributeType.MANY_TO_ONE
: mapKeyType.isComponentType()
? PersistentAttributeType.EMBEDDED
: PersistentAttributeType.BASIC;
}
private String determineRole(MapAttribute<?,K,?> attribute) {
return attribute.getDeclaringType().getJavaType().getName() +
'.' + attribute.getName();
}
@Override
public String getName() {
// TODO : ???
return "map-key";
}
@Override
public PersistentAttributeType getPersistentAttributeType() {
return persistentAttributeType;
}
@Override
public ManagedType<Map<K, ?>> getDeclaringType() {
// TODO : ???
return null;
}
@Override
public Class<K> getJavaType() {
return attribute.getKeyJavaType();
}
@Override
public Member getJavaMember() {
// TODO : ???
return null;
}
@Override
public boolean isAssociation() {
return mapKeyType.isEntityType();
}
@Override
public boolean isCollection() {
return false;
}
@Override
public boolean isId() {
return false;
}
@Override
public boolean isVersion() {
return false;
}
@Override
public boolean isOptional() {
return false;
}
@Override
public Type<K> getType() {
return jpaType;
}
@Override
public BindableType getBindableType() {
return jpaBindableType;
}
@Override
public Class<K> getBindableJavaType() {
return jpaBinableJavaType;
}
}
}