/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008, Red Hat Middleware LLC 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 Middleware LLC.
*
* 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.hql.internal.ast.tree;
import org.hibernate.engine.internal.JoinSequence;
import org.hibernate.internal.CoreMessageLogger;
import org.hibernate.hql.internal.antlr.SqlTokenTypes;
import org.hibernate.hql.internal.ast.util.ASTUtil;
import org.hibernate.hql.internal.ast.util.AliasGenerator;
import org.hibernate.hql.internal.ast.util.PathHelper;
import org.hibernate.hql.internal.ast.util.SessionFactoryHelper;
import org.hibernate.internal.util.StringHelper;
import org.hibernate.persister.collection.QueryableCollection;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.persister.entity.Joinable;
import org.hibernate.persister.entity.Queryable;
import org.hibernate.sql.JoinFragment;
import org.hibernate.sql.JoinType;
import org.hibernate.type.AssociationType;
import org.hibernate.type.CollectionType;
import org.hibernate.type.ComponentType;
import org.hibernate.type.EntityType;
import org.hibernate.type.Type;
import org.jboss.logging.Logger;
import antlr.ASTFactory;
import antlr.SemanticException;
import antlr.collections.AST;
/**
* Encapsulates the creation of FromElements and JoinSequences.
*
* @author josh
*/
public class FromElementFactory implements SqlTokenTypes {
private static final CoreMessageLogger LOG = Logger.getMessageLogger(CoreMessageLogger.class, FromElementFactory.class.getName());
private FromClause fromClause;
private FromElement origin;
private String path;
private String classAlias;
private String[] columns;
private boolean implied;
private boolean inElementsFunction;
private boolean collection;
private QueryableCollection queryableCollection;
private CollectionType collectionType;
/**
* Creates entity from elements.
*/
public FromElementFactory(FromClause fromClause, FromElement origin, String path) {
this.fromClause = fromClause;
this.origin = origin;
this.path = path;
collection = false;
}
/**
* Creates collection from elements.
*/
public FromElementFactory(
FromClause fromClause,
FromElement origin,
String path,
String classAlias,
String[] columns,
boolean implied) {
this( fromClause, origin, path );
this.classAlias = classAlias;
this.columns = columns;
this.implied = implied;
collection = true;
}
FromElement addFromElement() throws SemanticException {
FromClause parentFromClause = fromClause.getParentFromClause();
if ( parentFromClause != null ) {
// Look up class name using the first identifier in the path.
String pathAlias = PathHelper.getAlias( path );
FromElement parentFromElement = parentFromClause.getFromElement( pathAlias );
if ( parentFromElement != null ) {
return createFromElementInSubselect( path, pathAlias, parentFromElement, classAlias );
}
}
EntityPersister entityPersister = fromClause.getSessionFactoryHelper().requireClassPersister( path );
FromElement elem = createAndAddFromElement( path,
classAlias,
entityPersister,
( EntityType ) ( ( Queryable ) entityPersister ).getType(),
null );
// Add to the query spaces.
fromClause.getWalker().addQuerySpaces( entityPersister.getQuerySpaces() );
return elem;
}
private FromElement createFromElementInSubselect(
String path,
String pathAlias,
FromElement parentFromElement,
String classAlias) throws SemanticException {
LOG.debugf("createFromElementInSubselect() : path = %s", path);
// Create an DotNode AST for the path and resolve it.
FromElement fromElement = evaluateFromElementPath( path, classAlias );
EntityPersister entityPersister = fromElement.getEntityPersister();
// If the first identifier in the path refers to the class alias (not the class name), then this
// is a correlated subselect. If it's a correlated sub-select, use the existing table alias. Otherwise
// generate a new one.
String tableAlias = null;
boolean correlatedSubselect = pathAlias.equals( parentFromElement.getClassAlias() );
if ( correlatedSubselect ) {
tableAlias = fromElement.getTableAlias();
}
else {
tableAlias = null;
}
// If the from element isn't in the same clause, create a new from element.
if ( fromElement.getFromClause() != fromClause ) {
LOG.debugf("createFromElementInSubselect() : creating a new FROM element...");
fromElement = createFromElement( entityPersister );
initializeAndAddFromElement( fromElement,
path,
classAlias,
entityPersister,
( EntityType ) ( ( Queryable ) entityPersister ).getType(),
tableAlias
);
}
LOG.debugf("createFromElementInSubselect() : %s -> %s", path, fromElement);
return fromElement;
}
private FromElement evaluateFromElementPath(String path, String classAlias) throws SemanticException {
ASTFactory factory = fromClause.getASTFactory();
FromReferenceNode pathNode = ( FromReferenceNode ) PathHelper.parsePath( path, factory );
pathNode.recursiveResolve( FromReferenceNode.ROOT_LEVEL, // This is the root level node.
false, // Generate an explicit from clause at the root.
classAlias,
null
);
if (pathNode.getImpliedJoin() != null) return pathNode.getImpliedJoin();
return pathNode.getFromElement();
}
FromElement createCollectionElementsJoin(
QueryableCollection queryableCollection,
String collectionName) throws SemanticException {
JoinSequence collectionJoinSequence = fromClause.getSessionFactoryHelper()
.createCollectionJoinSequence( queryableCollection, collectionName );
this.queryableCollection = queryableCollection;
return createCollectionJoin( collectionJoinSequence, null );
}
FromElement createCollection(
QueryableCollection queryableCollection,
String role,
JoinType joinType,
boolean fetchFlag,
boolean indexed)
throws SemanticException {
if ( !collection ) {
throw new IllegalStateException( "FromElementFactory not initialized for collections!" );
}
this.inElementsFunction = indexed;
FromElement elem;
this.queryableCollection = queryableCollection;
collectionType = queryableCollection.getCollectionType();
String roleAlias = fromClause.getAliasGenerator().createName( role );
// Correlated subqueries create 'special' implied from nodes
// because correlated subselects can't use an ANSI-style join
boolean explicitSubqueryFromElement = fromClause.isSubQuery() && !implied;
if ( explicitSubqueryFromElement ) {
String pathRoot = StringHelper.root( path );
FromElement origin = fromClause.getFromElement( pathRoot );
if ( origin == null || origin.getFromClause() != fromClause ) {
implied = true;
}
}
// super-duper-classic-parser-regression-testing-mojo-magic...
if ( explicitSubqueryFromElement && DotNode.useThetaStyleImplicitJoins ) {
implied = true;
}
Type elementType = queryableCollection.getElementType();
if ( elementType.isEntityType() ) { // A collection of entities...
elem = createEntityAssociation( role, roleAlias, joinType );
}
else if ( elementType.isComponentType() ) { // A collection of components...
JoinSequence joinSequence = createJoinSequence( roleAlias, joinType );
elem = createCollectionJoin( joinSequence, roleAlias );
}
else { // A collection of scalar elements...
JoinSequence joinSequence = createJoinSequence( roleAlias, joinType );
elem = createCollectionJoin( joinSequence, roleAlias );
}
elem.setRole( role );
elem.setQueryableCollection( queryableCollection );
// Don't include sub-classes for implied collection joins or subquery joins.
if ( implied ) {
elem.setIncludeSubclasses( false );
}
if ( explicitSubqueryFromElement ) {
elem.setInProjectionList( true ); // Treat explict from elements in sub-queries properly.
}
if ( fetchFlag ) {
elem.setFetch( true );
}
return elem;
}
FromElement createEntityJoin(
String entityClass,
String tableAlias,
JoinSequence joinSequence,
boolean fetchFlag,
boolean inFrom,
EntityType type) throws SemanticException {
FromElement elem = createJoin( entityClass, tableAlias, joinSequence, type, false );
elem.setFetch( fetchFlag );
EntityPersister entityPersister = elem.getEntityPersister();
int numberOfTables = entityPersister.getQuerySpaces().length;
if ( numberOfTables > 1 && implied && !elem.useFromFragment() ) {
LOG.debugf("createEntityJoin() : Implied multi-table entity join");
elem.setUseFromFragment( true );
}
// If this is an implied join in a FROM clause, then use ANSI-style joining, and set the
// flag on the FromElement that indicates that it was implied in the FROM clause itself.
if ( implied && inFrom ) {
joinSequence.setUseThetaStyle( false );
elem.setUseFromFragment( true );
elem.setImpliedInFromClause( true );
}
if ( elem.getWalker().isSubQuery() ) {
// two conditions where we need to transform this to a theta-join syntax:
// 1) 'elem' is the "root from-element" in correlated subqueries
// 2) The DotNode.useThetaStyleImplicitJoins has been set to true
// and 'elem' represents an implicit join
if ( elem.getFromClause() != elem.getOrigin().getFromClause() ||
// ( implied && DotNode.useThetaStyleImplicitJoins ) ) {
DotNode.useThetaStyleImplicitJoins ) {
// the "root from-element" in correlated subqueries do need this piece
elem.setType( FROM_FRAGMENT );
joinSequence.setUseThetaStyle( true );
elem.setUseFromFragment( false );
}
}
return elem;
}
public FromElement createComponentJoin(ComponentType type) {
// need to create a "place holder" from-element that can store the component/alias for this
// component join
return new ComponentJoin( fromClause, origin, classAlias, path, type );
}
FromElement createElementJoin(QueryableCollection queryableCollection) throws SemanticException {
FromElement elem;
implied = true; //TODO: always true for now, but not if we later decide to support elements() in the from clause
inElementsFunction = true;
Type elementType = queryableCollection.getElementType();
if ( !elementType.isEntityType() ) {
throw new IllegalArgumentException( "Cannot create element join for a collection of non-entities!" );
}
this.queryableCollection = queryableCollection;
SessionFactoryHelper sfh = fromClause.getSessionFactoryHelper();
FromElement destination = null;
String tableAlias = null;
EntityPersister entityPersister = queryableCollection.getElementPersister();
tableAlias = fromClause.getAliasGenerator().createName( entityPersister.getEntityName() );
String associatedEntityName = entityPersister.getEntityName();
EntityPersister targetEntityPersister = sfh.requireClassPersister( associatedEntityName );
// Create the FROM element for the target (the elements of the collection).
destination = createAndAddFromElement(
associatedEntityName,
classAlias,
targetEntityPersister,
( EntityType ) queryableCollection.getElementType(),
tableAlias
);
// If the join is implied, then don't include sub-classes on the element.
if ( implied ) {
destination.setIncludeSubclasses( false );
}
fromClause.addCollectionJoinFromElementByPath( path, destination );
// origin.addDestination(destination);
// Add the query spaces.
fromClause.getWalker().addQuerySpaces( entityPersister.getQuerySpaces() );
CollectionType type = queryableCollection.getCollectionType();
String role = type.getRole();
String roleAlias = origin.getTableAlias();
String[] targetColumns = sfh.getCollectionElementColumns( role, roleAlias );
AssociationType elementAssociationType = sfh.getElementAssociationType( type );
// Create the join element under the from element.
JoinType joinType = JoinType.INNER_JOIN;
JoinSequence joinSequence = sfh.createJoinSequence( implied, elementAssociationType, tableAlias, joinType, targetColumns );
elem = initializeJoin( path, destination, joinSequence, targetColumns, origin, false );
elem.setUseFromFragment( true ); // The associated entity is implied, but it must be included in the FROM.
elem.setCollectionTableAlias( roleAlias ); // The collection alias is the role.
return elem;
}
private FromElement createCollectionJoin(JoinSequence collectionJoinSequence, String tableAlias) throws SemanticException {
String text = queryableCollection.getTableName();
AST ast = createFromElement( text );
FromElement destination = ( FromElement ) ast;
Type elementType = queryableCollection.getElementType();
if ( elementType.isCollectionType() ) {
throw new SemanticException( "Collections of collections are not supported!" );
}
destination.initializeCollection( fromClause, classAlias, tableAlias );
destination.setType( JOIN_FRAGMENT ); // Tag this node as a JOIN.
destination.setIncludeSubclasses( false ); // Don't include subclasses in the join.
destination.setCollectionJoin( true ); // This is a clollection join.
destination.setJoinSequence( collectionJoinSequence );
destination.setOrigin( origin, false );
destination.setCollectionTableAlias(tableAlias);
// origin.addDestination( destination );
// This was the cause of HHH-242
// origin.setType( FROM_FRAGMENT ); // Set the parent node type so that the AST is properly formed.
origin.setText( "" ); // The destination node will have all the FROM text.
origin.setCollectionJoin( true ); // The parent node is a collection join too (voodoo - see JoinProcessor)
fromClause.addCollectionJoinFromElementByPath( path, destination );
fromClause.getWalker().addQuerySpaces( queryableCollection.getCollectionSpaces() );
return destination;
}
private FromElement createEntityAssociation(
String role,
String roleAlias,
JoinType joinType) throws SemanticException {
FromElement elem;
Queryable entityPersister = ( Queryable ) queryableCollection.getElementPersister();
String associatedEntityName = entityPersister.getEntityName();
// Get the class name of the associated entity.
if ( queryableCollection.isOneToMany() ) {
LOG.debugf("createEntityAssociation() : One to many - path = %s role = %s associatedEntityName = %s",
path,
role,
associatedEntityName);
JoinSequence joinSequence = createJoinSequence( roleAlias, joinType );
elem = createJoin( associatedEntityName, roleAlias, joinSequence, ( EntityType ) queryableCollection.getElementType(), false );
}
else {
LOG.debugf("createManyToMany() : path = %s role = %s associatedEntityName = %s", path, role, associatedEntityName);
elem = createManyToMany( role, associatedEntityName,
roleAlias, entityPersister, ( EntityType ) queryableCollection.getElementType(), joinType );
fromClause.getWalker().addQuerySpaces( queryableCollection.getCollectionSpaces() );
}
elem.setCollectionTableAlias( roleAlias );
return elem;
}
private FromElement createJoin(
String entityClass,
String tableAlias,
JoinSequence joinSequence,
EntityType type,
boolean manyToMany) throws SemanticException {
// origin, path, implied, columns, classAlias,
EntityPersister entityPersister = fromClause.getSessionFactoryHelper().requireClassPersister( entityClass );
FromElement destination = createAndAddFromElement( entityClass,
classAlias,
entityPersister,
type,
tableAlias );
return initializeJoin( path, destination, joinSequence, getColumns(), origin, manyToMany );
}
private FromElement createManyToMany(
String role,
String associatedEntityName,
String roleAlias,
Queryable entityPersister,
EntityType type,
JoinType joinType) throws SemanticException {
FromElement elem;
SessionFactoryHelper sfh = fromClause.getSessionFactoryHelper();
if ( inElementsFunction /*implied*/ ) {
// For implied many-to-many, just add the end join.
JoinSequence joinSequence = createJoinSequence( roleAlias, joinType );
elem = createJoin( associatedEntityName, roleAlias, joinSequence, type, true );
}
else {
// For an explicit many-to-many relationship, add a second join from the intermediate
// (many-to-many) table to the destination table. Also, make sure that the from element's
// idea of the destination is the destination table.
String tableAlias = fromClause.getAliasGenerator().createName( entityPersister.getEntityName() );
String[] secondJoinColumns = sfh.getCollectionElementColumns( role, roleAlias );
// Add the second join, the one that ends in the destination table.
JoinSequence joinSequence = createJoinSequence( roleAlias, joinType );
joinSequence.addJoin( sfh.getElementAssociationType( collectionType ), tableAlias, joinType, secondJoinColumns );
elem = createJoin( associatedEntityName, tableAlias, joinSequence, type, false );
elem.setUseFromFragment( true );
}
return elem;
}
private JoinSequence createJoinSequence(String roleAlias, JoinType joinType) {
SessionFactoryHelper sessionFactoryHelper = fromClause.getSessionFactoryHelper();
String[] joinColumns = getColumns();
if ( collectionType == null ) {
throw new IllegalStateException( "collectionType is null!" );
}
return sessionFactoryHelper.createJoinSequence( implied, collectionType, roleAlias, joinType, joinColumns );
}
private FromElement createAndAddFromElement(
String className,
String classAlias,
EntityPersister entityPersister,
EntityType type,
String tableAlias) {
if ( !( entityPersister instanceof Joinable ) ) {
throw new IllegalArgumentException( "EntityPersister " + entityPersister + " does not implement Joinable!" );
}
FromElement element = createFromElement( entityPersister );
initializeAndAddFromElement( element, className, classAlias, entityPersister, type, tableAlias );
return element;
}
private void initializeAndAddFromElement(
FromElement element,
String className,
String classAlias,
EntityPersister entityPersister,
EntityType type,
String tableAlias) {
if ( tableAlias == null ) {
AliasGenerator aliasGenerator = fromClause.getAliasGenerator();
tableAlias = aliasGenerator.createName( entityPersister.getEntityName() );
}
element.initializeEntity( fromClause, className, entityPersister, type, classAlias, tableAlias );
}
private FromElement createFromElement(EntityPersister entityPersister) {
Joinable joinable = ( Joinable ) entityPersister;
String text = joinable.getTableName();
AST ast = createFromElement( text );
FromElement element = ( FromElement ) ast;
return element;
}
private AST createFromElement(String text) {
AST ast = ASTUtil.create( fromClause.getASTFactory(),
implied ? IMPLIED_FROM : FROM_FRAGMENT, // This causes the factory to instantiate the desired class.
text );
// Reset the node type, because the rest of the system is expecting FROM_FRAGMENT, all we wanted was
// for the factory to create the right sub-class. This might get reset again later on anyway to make the
// SQL generation simpler.
ast.setType( FROM_FRAGMENT );
return ast;
}
private FromElement initializeJoin(
String path,
FromElement destination,
JoinSequence joinSequence,
String[] columns,
FromElement origin,
boolean manyToMany) {
destination.setType( JOIN_FRAGMENT );
destination.setJoinSequence( joinSequence );
destination.setColumns( columns );
destination.setOrigin( origin, manyToMany );
fromClause.addJoinByPathMap( path, destination );
return destination;
}
private String[] getColumns() {
if ( columns == null ) {
throw new IllegalStateException( "No foriegn key columns were supplied!" );
}
return columns;
}
}