/*
* 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.ast.util;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.ListIterator;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;
import java.util.Collection;
import org.hibernate.AssertionFailure;
import org.hibernate.dialect.Dialect;
import org.hibernate.impl.FilterImpl;
import org.hibernate.type.Type;
import org.hibernate.param.DynamicFilterParameterSpecification;
import org.hibernate.param.CollectionFilterKeyParameterSpecification;
import org.hibernate.engine.JoinSequence;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.engine.LoadQueryInfluencers;
import org.hibernate.hql.antlr.SqlTokenTypes;
import org.hibernate.hql.ast.HqlSqlWalker;
import org.hibernate.hql.ast.tree.FromClause;
import org.hibernate.hql.ast.tree.FromElement;
import org.hibernate.hql.ast.tree.QueryNode;
import org.hibernate.hql.ast.tree.DotNode;
import org.hibernate.hql.ast.tree.ParameterContainer;
import org.hibernate.hql.classic.ParserHelper;
import org.hibernate.sql.JoinFragment;
import org.hibernate.util.StringHelper;
import org.hibernate.util.ArrayHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Performs the post-processing of the join information gathered during semantic analysis.
* The join generating classes are complex, this encapsulates some of the JoinSequence-related
* code.
*
* @author Joshua Davis
*/
public class JoinProcessor implements SqlTokenTypes {
private static final Logger log = LoggerFactory.getLogger( JoinProcessor.class );
private final HqlSqlWalker walker;
private final SyntheticAndFactory syntheticAndFactory;
/**
* Constructs a new JoinProcessor.
*
* @param walker The walker to which we are bound, giving us access to needed resources.
*/
public JoinProcessor(HqlSqlWalker walker) {
this.walker = walker;
this.syntheticAndFactory = new SyntheticAndFactory( walker );
}
/**
* Translates an AST join type (i.e., the token type) into a JoinFragment.XXX join type.
*
* @param astJoinType The AST join type (from HqlSqlTokenTypes or SqlTokenTypes)
* @return a JoinFragment.XXX join type.
* @see JoinFragment
* @see SqlTokenTypes
*/
public static int toHibernateJoinType(int astJoinType) {
switch ( astJoinType ) {
case LEFT_OUTER:
return JoinFragment.LEFT_OUTER_JOIN;
case INNER:
return JoinFragment.INNER_JOIN;
case RIGHT_OUTER:
return JoinFragment.RIGHT_OUTER_JOIN;
default:
throw new AssertionFailure( "undefined join type " + astJoinType );
}
}
public void processJoins(QueryNode query) {
final FromClause fromClause = query.getFromClause();
final List fromElements;
if ( DotNode.useThetaStyleImplicitJoins ) {
// for regression testing against output from the old parser...
// found it easiest to simply reorder the FromElements here into ascending order
// in terms of injecting them into the resulting sql ast in orders relative to those
// expected by the old parser; this is definitely another of those "only needed
// for regression purposes". The SyntheticAndFactory, then, simply injects them as it
// encounters them.
fromElements = new ArrayList();
ListIterator liter = fromClause.getFromElements().listIterator( fromClause.getFromElements().size() );
while ( liter.hasPrevious() ) {
fromElements.add( liter.previous() );
}
}
else {
fromElements = fromClause.getFromElements();
}
// Iterate through the alias,JoinSequence pairs and generate SQL token nodes.
Iterator iter = fromElements.iterator();
while ( iter.hasNext() ) {
final FromElement fromElement = ( FromElement ) iter.next();
JoinSequence join = fromElement.getJoinSequence();
join.setSelector(
new JoinSequence.Selector() {
public boolean includeSubclasses(String alias) {
// The uber-rule here is that we need to include subclass joins if
// the FromElement is in any way dereferenced by a property from
// the subclass table; otherwise we end up with column references
// qualified by a non-existent table reference in the resulting SQL...
boolean containsTableAlias = fromClause.containsTableAlias( alias );
if ( fromElement.isDereferencedBySubclassProperty() ) {
// TODO : or should we return 'containsTableAlias'??
log.trace( "forcing inclusion of extra joins [alias=" + alias + ", containsTableAlias=" + containsTableAlias + "]" );
return true;
}
boolean shallowQuery = walker.isShallowQuery();
boolean includeSubclasses = fromElement.isIncludeSubclasses();
boolean subQuery = fromClause.isSubQuery();
return includeSubclasses && containsTableAlias && !subQuery && !shallowQuery;
}
}
);
addJoinNodes( query, join, fromElement );
}
}
private void addJoinNodes(QueryNode query, JoinSequence join, FromElement fromElement) {
JoinFragment joinFragment = join.toJoinFragment(
walker.getEnabledFilters(),
fromElement.useFromFragment() || fromElement.isDereferencedBySuperclassOrSubclassProperty(),
fromElement.getWithClauseFragment(),
fromElement.getWithClauseJoinAlias()
);
String frag = joinFragment.toFromFragmentString();
String whereFrag = joinFragment.toWhereFragmentString();
// If the from element represents a JOIN_FRAGMENT and it is
// a theta-style join, convert its type from JOIN_FRAGMENT
// to FROM_FRAGMENT
if ( fromElement.getType() == JOIN_FRAGMENT &&
( join.isThetaStyle() || StringHelper.isNotEmpty( whereFrag ) ) ) {
fromElement.setType( FROM_FRAGMENT );
fromElement.getJoinSequence().setUseThetaStyle( true ); // this is used during SqlGenerator processing
}
// If there is a FROM fragment and the FROM element is an explicit, then add the from part.
if ( fromElement.useFromFragment() /*&& StringHelper.isNotEmpty( frag )*/ ) {
String fromFragment = processFromFragment( frag, join ).trim();
if ( log.isDebugEnabled() ) {
log.debug( "Using FROM fragment [" + fromFragment + "]" );
}
processDynamicFilterParameters(
fromFragment,
fromElement,
walker
);
}
syntheticAndFactory.addWhereFragment(
joinFragment,
whereFrag,
query,
fromElement,
walker
);
}
private String processFromFragment(String frag, JoinSequence join) {
String fromFragment = frag.trim();
// The FROM fragment will probably begin with ', '. Remove this if it is present.
if ( fromFragment.startsWith( ", " ) ) {
fromFragment = fromFragment.substring( 2 );
}
return fromFragment;
}
public static void processDynamicFilterParameters(
final String sqlFragment,
final ParameterContainer container,
final HqlSqlWalker walker) {
if ( walker.getEnabledFilters().isEmpty()
&& ( ! hasDynamicFilterParam( sqlFragment ) )
&& ( ! ( hasCollectionFilterParam( sqlFragment ) ) ) ) {
return;
}
Dialect dialect = walker.getSessionFactoryHelper().getFactory().getDialect();
String symbols = new StringBuffer().append( ParserHelper.HQL_SEPARATORS )
.append( dialect.openQuote() )
.append( dialect.closeQuote() )
.toString();
StringTokenizer tokens = new StringTokenizer( sqlFragment, symbols, true );
StringBuffer result = new StringBuffer();
while ( tokens.hasMoreTokens() ) {
final String token = tokens.nextToken();
if ( token.startsWith( ParserHelper.HQL_VARIABLE_PREFIX ) ) {
final String filterParameterName = token.substring( 1 );
final String[] parts = LoadQueryInfluencers.parseFilterParameterName( filterParameterName );
final FilterImpl filter = ( FilterImpl ) walker.getEnabledFilters().get( parts[0] );
final Object value = filter.getParameter( parts[1] );
final Type type = filter.getFilterDefinition().getParameterType( parts[1] );
final String typeBindFragment = StringHelper.join(
",",
ArrayHelper.fillArray( "?", type.getColumnSpan( walker.getSessionFactoryHelper().getFactory() ) )
);
final String bindFragment = ( value != null && Collection.class.isInstance( value ) )
? StringHelper.join( ",", ArrayHelper.fillArray( typeBindFragment, ( ( Collection ) value ).size() ) )
: typeBindFragment;
result.append( bindFragment );
container.addEmbeddedParameter( new DynamicFilterParameterSpecification( parts[0], parts[1], type ) );
}
else {
result.append( token );
}
}
container.setText( result.toString() );
}
private static boolean hasDynamicFilterParam(String sqlFragment) {
return sqlFragment.indexOf( ParserHelper.HQL_VARIABLE_PREFIX ) < 0;
}
private static boolean hasCollectionFilterParam(String sqlFragment) {
return sqlFragment.indexOf( "?" ) < 0;
}
}