// $Id: SessionFactoryHelper.java 10825 2006-11-16 19:33:19Z [email protected] $
package org.hibernate.hql.ast.util;
import java.util.HashMap;
import java.util.Map;
import org.hibernate.MappingException;
import org.hibernate.QueryException;
import org.hibernate.dialect.function.SQLFunction;
import org.hibernate.engine.JoinSequence;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.hql.NameGenerator;
import org.hibernate.hql.ast.DetailedSemanticException;
import org.hibernate.hql.ast.QuerySyntaxException;
import org.hibernate.hql.ast.tree.SqlNode;
import org.hibernate.persister.collection.CollectionPropertyMapping;
import org.hibernate.persister.collection.CollectionPropertyNames;
import org.hibernate.persister.collection.QueryableCollection;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.persister.entity.PropertyMapping;
import org.hibernate.persister.entity.Queryable;
import org.hibernate.type.AssociationType;
import org.hibernate.type.CollectionType;
import org.hibernate.type.EntityType;
import org.hibernate.type.Type;
import org.hibernate.type.TypeFactory;
import antlr.SemanticException;
import antlr.collections.AST;
/**
* Helper for performing common and/or complex operations with the
* {@link SessionFactoryImplementor} during translation of an HQL query.
*
* @author Joshua Davis
*/
public class SessionFactoryHelper {
private SessionFactoryImplementor sfi;
private Map collectionPropertyMappingByRole;
/**
* Construct a new SessionFactoryHelper instance.
*
* @param sfi The SessionFactory impl to be encapsualted.
*/
public SessionFactoryHelper(SessionFactoryImplementor sfi) {
this.sfi = sfi;
collectionPropertyMappingByRole = new HashMap();
}
/**
* Get a handle to the encapsulated SessionFactory.
*
* @return The encapsulated SessionFactory.
*/
public SessionFactoryImplementor getFactory() {
return sfi;
}
/**
* Does the given persister define a physical discriminator column
* for the purpose of inheritence discrimination?
*
* @param persister The persister to be checked.
* @return True if the persister does define an actual discriminator column.
*/
public boolean hasPhysicalDiscriminatorColumn(Queryable persister) {
if ( persister.getDiscriminatorType() != null ) {
String discrimColumnName = persister.getDiscriminatorColumnName();
// Needed the "clazz_" check to work around union-subclasses
// TODO : is there a way to tell whether a persister is truly discrim-column based inheritence?
if ( discrimColumnName != null && !"clazz_".equals( discrimColumnName ) ) {
return true;
}
}
return false;
}
/**
* Given a (potentially unqualified) class name, locate its imported qualified name.
*
* @param className The potentially unqualified class name
* @return The qualified class name.
*/
public String getImportedClassName(String className) {
return sfi.getImportedClassName( className );
}
/**
* Given a (potentially unqualified) class name, locate its persister.
*
* @param className The (potentially unqualified) class name.
* @return The defined persister for this class, or null if none found.
*/
public Queryable findQueryableUsingImports(String className) {
return findQueryableUsingImports( sfi, className );
}
/**
* Given a (potentially unqualified) class name, locate its persister.
*
* @param sfi The session factory implementor.
* @param className The (potentially unqualified) class name.
* @return The defined persister for this class, or null if none found.
*/
public static Queryable findQueryableUsingImports(SessionFactoryImplementor sfi, String className) {
final String importedClassName = sfi.getImportedClassName( className );
if ( importedClassName == null ) {
return null;
}
try {
return ( Queryable ) sfi.getEntityPersister( importedClassName );
}
catch ( MappingException me ) {
return null;
}
}
/**
* Locate the persister by class or entity name.
*
* @param name The class or entity name
* @return The defined persister for this entity, or null if none found.
* @throws MappingException
*/
private EntityPersister findEntityPersisterByName(String name) throws MappingException {
// First, try to get the persister using the given name directly.
try {
return sfi.getEntityPersister( name );
}
catch ( MappingException ignore ) {
// unable to locate it using this name
}
// If that didn't work, try using the 'import' name.
String importedClassName = sfi.getImportedClassName( name );
if ( importedClassName == null ) {
return null;
}
return sfi.getEntityPersister( importedClassName );
}
/**
* Locate the persister by class or entity name, requiring that such a persister
* exist.
*
* @param name The class or entity name
* @return The defined persister for this entity
* @throws SemanticException Indicates the persister could not be found
*/
public EntityPersister requireClassPersister(String name) throws SemanticException {
EntityPersister cp;
try {
cp = findEntityPersisterByName( name );
if ( cp == null ) {
throw new QuerySyntaxException( name + " is not mapped" );
}
}
catch ( MappingException e ) {
throw new DetailedSemanticException( e.getMessage(), e );
}
return cp;
}
/**
* Locate the collection persister by the collection role.
*
* @param role The collection role name.
* @return The defined CollectionPersister for this collection role, or null.
*/
public QueryableCollection getCollectionPersister(String role) {
try {
return ( QueryableCollection ) sfi.getCollectionPersister( role );
}
catch ( ClassCastException cce ) {
throw new QueryException( "collection is not queryable: " + role );
}
catch ( Exception e ) {
throw new QueryException( "collection not found: " + role );
}
}
/**
* Locate the collection persister by the collection role, requiring that
* such a persister exist.
*
* @param role The collection role name.
* @return The defined CollectionPersister for this collection role.
* @throws QueryException Indicates that the collection persister could not be found.
*/
public QueryableCollection requireQueryableCollection(String role) throws QueryException {
try {
QueryableCollection queryableCollection = ( QueryableCollection ) sfi.getCollectionPersister( role );
if ( queryableCollection != null ) {
collectionPropertyMappingByRole.put( role, new CollectionPropertyMapping( queryableCollection ) );
}
return queryableCollection;
}
catch ( ClassCastException cce ) {
throw new QueryException( "collection role is not queryable: " + role );
}
catch ( Exception e ) {
throw new QueryException( "collection role not found: " + role );
}
}
/**
* Retreive a PropertyMapping describing the given collection role.
*
* @param role The collection role for whcih to retrieve the property mapping.
* @return The property mapping.
*/
private PropertyMapping getCollectionPropertyMapping(String role) {
return ( PropertyMapping ) collectionPropertyMappingByRole.get( role );
}
/**
* Retrieves the column names corresponding to the collection elements for the given
* collection role.
*
* @param role The collection role
* @param roleAlias The sql column-qualification alias (i.e., the table alias)
* @return the collection element columns
*/
public String[] getCollectionElementColumns(String role, String roleAlias) {
return getCollectionPropertyMapping( role ).toColumns( roleAlias, CollectionPropertyNames.COLLECTION_ELEMENTS );
}
/**
* Generate an empty join sequence instance.
*
* @return The generate join sequence.
*/
public JoinSequence createJoinSequence() {
return new JoinSequence( sfi );
}
/**
* Generate a join sequence representing the given association type.
*
* @param implicit Should implicit joins (theta-style) or explicit joins (ANSI-style) be rendered
* @param associationType The type representing the thing to be joined into.
* @param tableAlias The table alias to use in qualifing the join conditions
* @param joinType The type of join to render (inner, outer, etc); see {@link org.hibernate.sql.JoinFragment}
* @param columns The columns making up the condition of the join.
* @return The generated join sequence.
*/
public JoinSequence createJoinSequence(boolean implicit, AssociationType associationType, String tableAlias, int joinType, String[] columns) {
JoinSequence joinSequence = createJoinSequence();
joinSequence.setUseThetaStyle( implicit ); // Implicit joins use theta style (WHERE pk = fk), explicit joins use JOIN (after from)
joinSequence.addJoin( associationType, tableAlias, joinType, columns );
return joinSequence;
}
/**
* Create a join sequence rooted at the given collection.
*
* @param collPersister The persister for the collection at which the join should be rooted.
* @param collectionName The alias to use for qualifying column references.
* @return The generated join sequence.
*/
public JoinSequence createCollectionJoinSequence(QueryableCollection collPersister, String collectionName) {
JoinSequence joinSequence = createJoinSequence();
joinSequence.setRoot( collPersister, collectionName );
joinSequence.setUseThetaStyle( true ); // TODO: figure out how this should be set.
///////////////////////////////////////////////////////////////////////////////
// This was the reason for failures regarding INDEX_OP and subclass joins on
// theta-join dialects; not sure what behaviour we were trying to emulate ;)
// joinSequence = joinSequence.getFromPart(); // Emulate the old addFromOnly behavior.
return joinSequence;
}
/**
* Determine the name of the property for the entity encapsulated by the
* given type which represents the id or unique-key.
*
* @param entityType The type representing the entity.
* @return The corresponding property name
* @throws QueryException Indicates such a property could not be found.
*/
public String getIdentifierOrUniqueKeyPropertyName(EntityType entityType) {
try {
return entityType.getIdentifierOrUniqueKeyPropertyName( sfi );
}
catch ( MappingException me ) {
throw new QueryException( me );
}
}
/**
* Retreive the number of columns represented by this type.
*
* @param type The type.
* @return The number of columns.
*/
public int getColumnSpan(Type type) {
return type.getColumnSpan( sfi );
}
/**
* Given a collection type, determine the entity name of the elements
* contained within instance of that collection.
*
* @param collectionType The collection type to check.
* @return The entity name of the elements of this collection.
*/
public String getAssociatedEntityName(CollectionType collectionType) {
return collectionType.getAssociatedEntityName( sfi );
}
/**
* Given a collection type, determine the Type representing elements
* within instances of that collection.
*
* @param collectionType The collection type to be checked.
* @return The Type of the elements of the collection.
*/
private Type getElementType(CollectionType collectionType) {
return collectionType.getElementType( sfi );
}
/**
* Essentially the same as {@link #getElementType}, but requiring that the
* element type be an association type.
*
* @param collectionType The collection type to be checked.
* @return The AssociationType of the elements of the collection.
*/
public AssociationType getElementAssociationType(CollectionType collectionType) {
return ( AssociationType ) getElementType( collectionType );
}
/**
* Locate a registered sql function by name.
*
* @param functionName The name of the function to locate
* @return The sql function, or null if not found.
*/
public SQLFunction findSQLFunction(String functionName) {
return sfi.getSqlFunctionRegistry().findSQLFunction( functionName.toLowerCase() );
}
/**
* Locate a registered sql function by name, requiring that such a registered function exist.
*
* @param functionName The name of the function to locate
* @return The sql function.
* @throws QueryException Indicates no matching sql functions could be found.
*/
private SQLFunction requireSQLFunction(String functionName) {
SQLFunction f = findSQLFunction( functionName );
if ( f == null ) {
throw new QueryException( "Unable to find SQL function: " + functionName );
}
return f;
}
/**
* Find the function return type given the function name and the first argument expression node.
*
* @param functionName The function name.
* @param first The first argument expression.
* @return the function return type given the function name and the first argument expression node.
*/
public Type findFunctionReturnType(String functionName, AST first) {
// locate the registered function by the given name
SQLFunction sqlFunction = requireSQLFunction( functionName );
// determine the type of the first argument...
Type argumentType = null;
if ( first != null ) {
if ( "cast".equals(functionName) ) {
argumentType = TypeFactory.heuristicType( first.getNextSibling().getText() );
}
else if ( first instanceof SqlNode ) {
argumentType = ( (SqlNode) first ).getDataType();
}
}
return sqlFunction.getReturnType( argumentType, sfi );
}
public String[][] generateColumnNames(Type[] sqlResultTypes) {
return NameGenerator.generateColumnNames( sqlResultTypes, sfi );
}
public boolean isStrictJPAQLComplianceEnabled() {
return sfi.getSettings().isStrictJPAQLCompliance();
}
}
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