/* * Hibernate, Relational Persistence for Idiomatic Java * * License: GNU Lesser General Public License (LGPL), version 2.1 or later. * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>. */ package org.hibernate.hql.internal.ast.tree; import org.hibernate.QueryException; import org.hibernate.engine.internal.JoinSequence; import org.hibernate.hql.internal.CollectionProperties; import org.hibernate.hql.internal.antlr.SqlTokenTypes; import org.hibernate.hql.internal.ast.util.ASTUtil; import org.hibernate.hql.internal.ast.util.ColumnHelper; import org.hibernate.internal.CoreLogging; import org.hibernate.internal.CoreMessageLogger; import org.hibernate.internal.log.DeprecationLogger; import org.hibernate.internal.util.StringHelper; import org.hibernate.persister.collection.QueryableCollection; import org.hibernate.persister.entity.AbstractEntityPersister; import org.hibernate.persister.entity.EntityPersister; import org.hibernate.persister.entity.Queryable; import org.hibernate.sql.JoinType; import org.hibernate.type.CollectionType; import org.hibernate.type.EntityType; import org.hibernate.type.Type; import antlr.SemanticException; import antlr.collections.AST; /** * Represents a reference to a property or alias expression. This should duplicate the relevant behaviors in * PathExpressionParser. * * @author Joshua Davis */ public class DotNode extends FromReferenceNode implements DisplayableNode, SelectExpression { private static final CoreMessageLogger LOG = CoreLogging.messageLogger( DotNode.class ); /////////////////////////////////////////////////////////////////////////// // USED ONLY FOR REGRESSION TESTING!!!! // // todo : obviously get rid of all this junk ;) /////////////////////////////////////////////////////////////////////////// public static boolean useThetaStyleImplicitJoins; public static boolean regressionStyleJoinSuppression; public interface IllegalCollectionDereferenceExceptionBuilder { QueryException buildIllegalCollectionDereferenceException( String collectionPropertyName, FromReferenceNode lhs); } public static final IllegalCollectionDereferenceExceptionBuilder DEF_ILLEGAL_COLL_DEREF_EXCP_BUILDER = new IllegalCollectionDereferenceExceptionBuilder() { public QueryException buildIllegalCollectionDereferenceException(String propertyName, FromReferenceNode lhs) { String lhsPath = ASTUtil.getPathText( lhs ); return new QueryException( "illegal attempt to dereference collection [" + lhsPath + "] with element property reference [" + propertyName + "]" ); } }; public static IllegalCollectionDereferenceExceptionBuilder ILLEGAL_COLL_DEREF_EXCP_BUILDER = DEF_ILLEGAL_COLL_DEREF_EXCP_BUILDER; /////////////////////////////////////////////////////////////////////////// public static enum DereferenceType { UNKNOWN, ENTITY, COMPONENT, COLLECTION, PRIMITIVE, IDENTIFIER, JAVA_CONSTANT } /** * The identifier that is the name of the property. */ private String propertyName; /** * The full path, to the root alias of this dot node. */ private String path; /** * The unresolved property path relative to this dot node. */ private String propertyPath; /** * The column names that this resolves to. */ private String[] columns; /** * The type of join to create. Default is an inner join. */ private JoinType joinType = JoinType.INNER_JOIN; /** * Fetch join or not. */ private boolean fetch; /** * The type of dereference that hapened */ private DereferenceType dereferenceType = DereferenceType.UNKNOWN; private FromElement impliedJoin; /** * Sets the join type for this '.' node structure. * * @param joinType The type of join to use. * * @see org.hibernate.sql.JoinFragment */ public void setJoinType(JoinType joinType) { this.joinType = joinType; } private String[] getColumns() throws QueryException { if ( columns == null ) { // Use the table fromElement and the property name to get the array of column names. String tableAlias = getLhs().getFromElement().getTableAlias(); columns = getFromElement().toColumns( tableAlias, propertyPath, false ); } return columns; } @Override public String getDisplayText() { StringBuilder buf = new StringBuilder(); FromElement fromElement = getFromElement(); buf.append( "{propertyName=" ).append( propertyName ); buf.append( ",dereferenceType=" ).append( dereferenceType.name() ); buf.append( ",getPropertyPath=" ).append( propertyPath ); buf.append( ",path=" ).append( getPath() ); if ( fromElement != null ) { buf.append( ",tableAlias=" ).append( fromElement.getTableAlias() ); buf.append( ",className=" ).append( fromElement.getClassName() ); buf.append( ",classAlias=" ).append( fromElement.getClassAlias() ); } else { buf.append( ",no from element" ); } buf.append( '}' ); return buf.toString(); } /** * Resolves the left hand side of the DOT. * * @throws SemanticException */ @Override public void resolveFirstChild() throws SemanticException { FromReferenceNode lhs = (FromReferenceNode) getFirstChild(); SqlNode property = (SqlNode) lhs.getNextSibling(); // Set the attributes of the property reference expression. String propName = property.getText(); propertyName = propName; // If the uresolved property path isn't set yet, just use the property name. if ( propertyPath == null ) { propertyPath = propName; } // Resolve the LHS fully, generate implicit joins. Pass in the property name so that the resolver can // discover foreign key (id) properties. lhs.resolve( true, true, null, this ); setFromElement( lhs.getFromElement() ); // The 'from element' that the property is in. checkSubclassOrSuperclassPropertyReference( lhs, propName ); } @Override public void resolveInFunctionCall(boolean generateJoin, boolean implicitJoin) throws SemanticException { if ( isResolved() ) { return; } Type propertyType = prepareLhs(); // Prepare the left hand side and get the data type. if ( propertyType != null && propertyType.isCollectionType() ) { resolveIndex( null ); } else { resolveFirstChild(); super.resolve( generateJoin, implicitJoin ); } } public void resolveIndex(AST parent) throws SemanticException { if ( isResolved() ) { return; } Type propertyType = prepareLhs(); // Prepare the left hand side and get the data type. dereferenceCollection( (CollectionType) propertyType, true, true, null, parent ); } public void resolve(boolean generateJoin, boolean implicitJoin, String classAlias, AST parent, AST parentPredicate) throws SemanticException { // If this dot has already been resolved, stop now. if ( isResolved() ) { return; } Type propertyType = prepareLhs(); // Prepare the left hand side and get the data type. if ( parent == null && AbstractEntityPersister.ENTITY_CLASS.equals( propertyName ) ) { DeprecationLogger.DEPRECATION_LOGGER.logDeprecationOfClassEntityTypeSelector( getLhs().getPath() ); } // If there is no data type for this node, and we're at the end of the path (top most dot node), then // this might be a Java constant. if ( propertyType == null ) { if ( parent == null ) { getWalker().getLiteralProcessor().lookupConstant( this ); } // If the propertyType is null and there isn't a parent, just // stop now... there was a problem resolving the node anyway. return; } if ( propertyType.isComponentType() ) { // The property is a component... checkLhsIsNotCollection(); dereferenceComponent( parent ); initText(); } else if ( propertyType.isEntityType() ) { // The property is another class.. checkLhsIsNotCollection(); dereferenceEntity( (EntityType) propertyType, implicitJoin, classAlias, generateJoin, parent, parentPredicate ); initText(); } else if ( propertyType.isCollectionType() ) { // The property is a collection... checkLhsIsNotCollection(); dereferenceCollection( (CollectionType) propertyType, implicitJoin, false, classAlias, parent ); } else { // Otherwise, this is a primitive type. if ( !CollectionProperties.isAnyCollectionProperty( propertyName ) ) { checkLhsIsNotCollection(); } dereferenceType = DereferenceType.PRIMITIVE; initText(); } setResolved(); } private void initText() { String[] cols = getColumns(); String text = StringHelper.join( ", ", cols ); boolean countDistinct = getWalker().isInCountDistinct() && getWalker().getSessionFactoryHelper().getFactory().getDialect().requiresParensForTupleDistinctCounts(); if ( cols.length > 1 && ( getWalker().isComparativeExpressionClause() || countDistinct ) ) { text = "(" + text + ")"; } setText( text ); } private Type prepareLhs() throws SemanticException { FromReferenceNode lhs = getLhs(); lhs.prepareForDot( propertyName ); return getDataType(); } private void dereferenceCollection( CollectionType collectionType, boolean implicitJoin, boolean indexed, String classAlias, AST parent) throws SemanticException { dereferenceType = DereferenceType.COLLECTION; String role = collectionType.getRole(); //foo.bars.size (also handles deprecated stuff like foo.bars.maxelement for backwardness) boolean isSizeProperty = getNextSibling() != null && CollectionProperties.isAnyCollectionProperty( getNextSibling().getText() ); if ( isSizeProperty ) { indexed = true; //yuck! } QueryableCollection queryableCollection = getSessionFactoryHelper().requireQueryableCollection( role ); String propName = getPath(); FromClause currentFromClause = getWalker().getCurrentFromClause(); // If the lhs of the join is a "component join", we need to go back to the // first non-component-join as the origin to properly link aliases and // join columns FromElement lhsFromElement = getLhs().getFromElement(); while ( lhsFromElement != null && ComponentJoin.class.isInstance( lhsFromElement ) ) { lhsFromElement = lhsFromElement.getOrigin(); } if ( lhsFromElement == null ) { throw new QueryException( "Unable to locate appropriate lhs" ); } // determine whether we should use the table name or table alias to qualify the column names... // we need to use the table-name when: // 1) the top-level statement is not a SELECT // 2) the LHS FromElement is *the* FromElement from the top-level statement // // there is a caveat here.. if the update/delete statement are "multi-table" we should continue to use // the alias also, even if the FromElement is the root one... // // in all other cases, we should use the table alias if ( getWalker().getStatementType() != SqlTokenTypes.SELECT ) { if ( isFromElementUpdateOrDeleteRoot( lhsFromElement ) ) { // at this point we know we have the 2 conditions above, // lets see if we have the mentioned "multi-table" caveat... boolean useAlias = false; if ( getWalker().getStatementType() != SqlTokenTypes.INSERT ) { final Queryable persister = lhsFromElement.getQueryable(); if ( persister.isMultiTable() ) { useAlias = true; } } if ( !useAlias ) { final String lhsTableName = lhsFromElement.getQueryable().getTableName(); columns = getFromElement().toColumns( lhsTableName, propertyPath, false, true ); } } } // We do not look for an existing join on the same path, because // it makes sense to join twice on the same collection role FromElementFactory factory = new FromElementFactory( currentFromClause, lhsFromElement, propName, classAlias, getColumns(), implicitJoin ); FromElement elem = factory.createCollection( queryableCollection, role, joinType, fetch, indexed ); LOG.debugf( "dereferenceCollection() : Created new FROM element for %s : %s", propName, elem ); setImpliedJoin( elem ); setFromElement( elem ); // This 'dot' expression now refers to the resulting from element. if ( isSizeProperty ) { elem.setText( "" ); elem.setUseWhereFragment( false ); } if ( !implicitJoin ) { EntityPersister entityPersister = elem.getEntityPersister(); if ( entityPersister != null ) { getWalker().addQuerySpaces( entityPersister.getQuerySpaces() ); } } getWalker().addQuerySpaces( queryableCollection.getCollectionSpaces() ); // Always add the collection's query spaces. } private void dereferenceEntity( EntityType entityType, boolean implicitJoin, String classAlias, boolean generateJoin, AST parent, AST parentPredicate) throws SemanticException { checkForCorrelatedSubquery( "dereferenceEntity" ); // three general cases we check here as to whether to render a physical SQL join: // 1) is our parent a DotNode as well? If so, our property reference is // being further de-referenced... // 2) is this a DML statement // 3) we were asked to generate any needed joins (generateJoins==true) *OR* // we are currently processing a select or from clause // (an additional check is the regressionStyleJoinSuppression check solely intended for the test suite) // // The regressionStyleJoinSuppression is an additional check // intended solely for use within the test suite. This forces the // implicit join resolution to behave more like the classic parser. // The underlying issue is that classic translator is simply wrong // about its decisions on whether or not to render an implicit join // into a physical SQL join in a lot of cases. The piece it generally // tends to miss is that INNER joins effect the results by further // restricting the data set! A particular manifestation of this is // the fact that the classic translator will skip the physical join // for ToOne implicit joins *if the query is shallow*; the result // being that Query.list() and Query.iterate() could return // different number of results! DotNode parentAsDotNode = null; String property = propertyName; final boolean joinIsNeeded; if ( isDotNode( parent ) ) { // our parent is another dot node, meaning we are being further dereferenced. // thus we need to generate a join unless the parent refers to the associated // entity's PK (because 'our' table would know the FK). parentAsDotNode = (DotNode) parent; property = parentAsDotNode.propertyName; joinIsNeeded = generateJoin && !isReferenceToPrimaryKey( parentAsDotNode.propertyName, entityType ); } else if ( !getWalker().isSelectStatement() ) { // in non-select queries, the only time we should need to join is if we are in a subquery from clause joinIsNeeded = getWalker().getCurrentStatementType() == SqlTokenTypes.SELECT && getWalker().isInFrom(); } else if ( regressionStyleJoinSuppression ) { // this is the regression style determination which matches the logic of the classic translator joinIsNeeded = generateJoin && ( !getWalker().isInSelect() || !getWalker().isShallowQuery() ); } else if ( parentPredicate != null ) { // Never generate a join when we compare entities directly joinIsNeeded = generateJoin; } else { joinIsNeeded = generateJoin || ( getWalker().isInSelect() || getWalker().isInFrom() ); } if ( joinIsNeeded ) { dereferenceEntityJoin( classAlias, entityType, implicitJoin, parent ); } else { dereferenceEntityIdentifier( property, parentAsDotNode ); } } private boolean isDotNode(AST n) { return n != null && n.getType() == SqlTokenTypes.DOT; } private void dereferenceEntityJoin(String classAlias, EntityType propertyType, boolean impliedJoin, AST parent) throws SemanticException { dereferenceType = DereferenceType.ENTITY; if ( LOG.isDebugEnabled() ) { LOG.debugf( "dereferenceEntityJoin() : generating join for %s in %s (%s) parent = %s", propertyName, getFromElement().getClassName(), classAlias == null ? "<no alias>" : classAlias, ASTUtil.getDebugString( parent ) ); } // Create a new FROM node for the referenced class. String associatedEntityName = propertyType.getAssociatedEntityName(); String tableAlias = getAliasGenerator().createName( associatedEntityName ); String[] joinColumns = getColumns(); String joinPath = getPath(); if ( impliedJoin && getWalker().isInFrom() ) { joinType = getWalker().getImpliedJoinType(); } FromClause currentFromClause = getWalker().getCurrentFromClause(); FromElement elem = currentFromClause.findJoinByPath( joinPath ); /////////////////////////////////////////////////////////////////////////////// // // This is the piece which recognizes the condition where an implicit join path // resolved earlier in a correlated subquery is now being referenced in the // outer query. For 3.0final, we just let this generate a second join (which // is exactly how the old parser handles this). Eventually we need to add this // logic back in and complete the logic in FromClause.promoteJoin; however, // FromClause.promoteJoin has its own difficulties (see the comments in // FromClause.promoteJoin). // // if ( elem == null ) { // // see if this joinPath has been used in a "child" FromClause, and if so // // promote that element to the outer query // FromClause currentNodeOwner = getFromElement().getFromClause(); // FromClause currentJoinOwner = currentNodeOwner.locateChildFromClauseWithJoinByPath( joinPath ); // if ( currentJoinOwner != null && currentNodeOwner != currentJoinOwner ) { // elem = currentJoinOwner.findJoinByPathLocal( joinPath ); // if ( elem != null ) { // currentFromClause.promoteJoin( elem ); // // EARLY EXIT!!! // return; // } // } // } // /////////////////////////////////////////////////////////////////////////////// boolean found = elem != null; // even though we might find a pre-existing element by join path, we may not be able to reuse it... boolean useFoundFromElement = found && canReuse( classAlias, elem ); if ( !useFoundFromElement ) { // If this is an implied join in a from element, then use the impled join type which is part of the // tree parser's state (set by the gramamar actions). JoinSequence joinSequence = getSessionFactoryHelper() .createJoinSequence( impliedJoin, propertyType, tableAlias, joinType, joinColumns ); // If the lhs of the join is a "component join", we need to go back to the // first non-component-join as the origin to properly link aliases and // join columns FromElement lhsFromElement = getLhs().getFromElement(); while ( lhsFromElement != null && ComponentJoin.class.isInstance( lhsFromElement ) ) { lhsFromElement = lhsFromElement.getOrigin(); } if ( lhsFromElement == null ) { throw new QueryException( "Unable to locate appropriate lhs" ); } String role = lhsFromElement.getClassName() + "." + propertyName; FromElementFactory factory = new FromElementFactory( currentFromClause, lhsFromElement, joinPath, classAlias, joinColumns, impliedJoin ); elem = factory.createEntityJoin( associatedEntityName, tableAlias, joinSequence, fetch, getWalker().isInFrom(), propertyType, role, joinPath ); } else { // NOTE : addDuplicateAlias() already performs nullness checks on the alias. currentFromClause.addDuplicateAlias( classAlias, elem ); } setImpliedJoin( elem ); getWalker().addQuerySpaces( elem.getEntityPersister().getQuerySpaces() ); setFromElement( elem ); // This 'dot' expression now refers to the resulting from element. } private boolean canReuse(String classAlias, FromElement fromElement) { // if the from-clauses are the same, we can be a little more aggressive in terms of what we reuse if ( fromElement.getFromClause() == getWalker().getCurrentFromClause() && areSame( classAlias, fromElement.getClassAlias() )) { return true; } // otherwise (subquery case) dont reuse the fromElement if we are processing the from-clause of the subquery return getWalker().getCurrentClauseType() != SqlTokenTypes.FROM; } private boolean areSame(String alias1, String alias2) { // again, null != null here return !StringHelper.isEmpty( alias1 ) && !StringHelper.isEmpty( alias2 ) && alias1.equals( alias2 ); } private void setImpliedJoin(FromElement elem) { this.impliedJoin = elem; if ( getFirstChild().getType() == SqlTokenTypes.DOT ) { DotNode dotLhs = (DotNode) getFirstChild(); if ( dotLhs.getImpliedJoin() != null ) { this.impliedJoin = dotLhs.getImpliedJoin(); } } } @Override public FromElement getImpliedJoin() { return impliedJoin; } /** * Is the given property name a reference to the primary key of the associated * entity construed by the given entity type? * <p/> * For example, consider a fragment like order.customer.id * (where order is a from-element alias). Here, we'd have: * propertyName = "id" AND * owningType = ManyToOneType(Customer) * and are being asked to determine whether "customer.id" is a reference * to customer's PK... * * @param propertyName The name of the property to check. * @param owningType The type represeting the entity "owning" the property * * @return True if propertyName references the entity's (owningType->associatedEntity) * primary key; false otherwise. */ private boolean isReferenceToPrimaryKey(String propertyName, EntityType owningType) { EntityPersister persister = getSessionFactoryHelper() .getFactory() .getEntityPersister( owningType.getAssociatedEntityName() ); if ( persister.getEntityMetamodel().hasNonIdentifierPropertyNamedId() ) { // only the identifier property field name can be a reference to the associated entity's PK... return propertyName.equals( persister.getIdentifierPropertyName() ) && owningType.isReferenceToPrimaryKey(); } // here, we have two possibilities: // 1) the property-name matches the explicitly identifier property name // 2) the property-name matches the implicit 'id' property name // the referenced node text is the special 'id' if ( EntityPersister.ENTITY_ID.equals( propertyName ) ) { return owningType.isReferenceToPrimaryKey(); } String keyPropertyName = getSessionFactoryHelper().getIdentifierOrUniqueKeyPropertyName( owningType ); return keyPropertyName != null && keyPropertyName.equals( propertyName ) && owningType.isReferenceToPrimaryKey(); } private void checkForCorrelatedSubquery(String methodName) { if ( isCorrelatedSubselect() ) { LOG.debugf( "%s() : correlated subquery", methodName ); } } private boolean isCorrelatedSubselect() { return getWalker().isSubQuery() && getFromElement().getFromClause() != getWalker().getCurrentFromClause(); } private void checkLhsIsNotCollection() throws SemanticException { if ( getLhs().getDataType() != null && getLhs().getDataType().isCollectionType() ) { throw ILLEGAL_COLL_DEREF_EXCP_BUILDER.buildIllegalCollectionDereferenceException( propertyName, getLhs() ); } } private void dereferenceComponent(AST parent) { dereferenceType = DereferenceType.COMPONENT; setPropertyNameAndPath( parent ); } private void dereferenceEntityIdentifier(String propertyName, DotNode dotParent) { // special shortcut for id properties, skip the join! // this must only occur at the _end_ of a path expression if ( LOG.isDebugEnabled() ) { LOG.debugf( "dereferenceShortcut() : property %s in %s does not require a join.", propertyName, getFromElement().getClassName() ); } initText(); setPropertyNameAndPath( dotParent ); // Set the unresolved path in this node and the parent. // Set the text for the parent. if ( dotParent != null ) { dotParent.dereferenceType = DereferenceType.IDENTIFIER; dotParent.setText( getText() ); dotParent.columns = getColumns(); } } private void setPropertyNameAndPath(AST parent) { if ( isDotNode( parent ) ) { DotNode dotNode = (DotNode) parent; AST lhs = dotNode.getFirstChild(); AST rhs = lhs.getNextSibling(); propertyName = rhs.getText(); propertyPath = propertyPath + "." + propertyName; // Append the new property name onto the unresolved path. dotNode.propertyPath = propertyPath; LOG.debugf( "Unresolved property path is now '%s'", dotNode.propertyPath ); } else { LOG.debugf( "Terminal getPropertyPath = [%s]", propertyPath ); } } @Override public Type getDataType() { if ( super.getDataType() == null ) { FromElement fromElement = getLhs().getFromElement(); if ( fromElement == null ) { return null; } // If the lhs is a collection, use CollectionPropertyMapping Type propertyType = fromElement.getPropertyType( propertyName, propertyPath ); LOG.debugf( "getDataType() : %s -> %s", propertyPath, propertyType ); super.setDataType( propertyType ); } return super.getDataType(); } public void setPropertyPath(String propertyPath) { this.propertyPath = propertyPath; } public String getPropertyPath() { return propertyPath; } public FromReferenceNode getLhs() { FromReferenceNode lhs = ( (FromReferenceNode) getFirstChild() ); if ( lhs == null ) { throw new IllegalStateException( "DOT node with no left-hand-side!" ); } return lhs; } /** * Returns the full path of the node. * * @return the full path of the node. */ @Override public String getPath() { if ( path == null ) { FromReferenceNode lhs = getLhs(); if ( lhs == null ) { path = getText(); } else { SqlNode rhs = (SqlNode) lhs.getNextSibling(); path = lhs.getPath() + "." + rhs.getOriginalText(); } } return path; } public void setFetch(boolean fetch) { this.fetch = fetch; } public void setScalarColumnText(int i) throws SemanticException { String[] sqlColumns = getColumns(); ColumnHelper.generateScalarColumns( this, sqlColumns, i ); } /** * Special method to resolve expressions in the SELECT list. * * @throws SemanticException if this cannot be resolved. */ public void resolveSelectExpression() throws SemanticException { if ( getWalker().isShallowQuery() || getWalker().getCurrentFromClause().isSubQuery() ) { resolve( false, true ); } else { resolve( true, false ); Type type = getDataType(); if ( type.isEntityType() ) { FromElement fromElement = getFromElement(); fromElement.setIncludeSubclasses( true ); // Tell the destination fromElement to 'includeSubclasses'. if ( useThetaStyleImplicitJoins ) { fromElement.getJoinSequence().setUseThetaStyle( true ); // Use theta style (for regression) // Move the node up, after the origin node. FromElement origin = fromElement.getOrigin(); if ( origin != null ) { ASTUtil.makeSiblingOfParent( origin, fromElement ); } } } } FromReferenceNode lhs = getLhs(); while ( lhs != null ) { checkSubclassOrSuperclassPropertyReference( lhs, lhs.getNextSibling().getText() ); lhs = (FromReferenceNode) lhs.getFirstChild(); } } public void setResolvedConstant(String text) { path = text; dereferenceType = DereferenceType.JAVA_CONSTANT; setResolved(); // Don't resolve the node again. } private boolean checkSubclassOrSuperclassPropertyReference(FromReferenceNode lhs, String propertyName) { if ( lhs != null && !( lhs instanceof IndexNode ) ) { final FromElement source = lhs.getFromElement(); if ( source != null ) { source.handlePropertyBeingDereferenced( lhs.getDataType(), propertyName ); } } return false; } }