/*
* 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.util;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import java.util.StringTokenizer;
import org.hibernate.AssertionFailure;
import org.hibernate.dialect.Dialect;
import org.hibernate.engine.internal.JoinSequence;
import org.hibernate.engine.spi.LoadQueryInfluencers;
import org.hibernate.hql.internal.antlr.SqlTokenTypes;
import org.hibernate.hql.internal.ast.HqlSqlWalker;
import org.hibernate.hql.internal.ast.tree.DotNode;
import org.hibernate.hql.internal.ast.tree.FromClause;
import org.hibernate.hql.internal.ast.tree.FromElement;
import org.hibernate.hql.internal.ast.tree.ImpliedFromElement;
import org.hibernate.hql.internal.ast.tree.ParameterContainer;
import org.hibernate.hql.internal.ast.tree.QueryNode;
import org.hibernate.hql.internal.classic.ParserHelper;
import org.hibernate.internal.CoreLogging;
import org.hibernate.internal.CoreMessageLogger;
import org.hibernate.internal.FilterImpl;
import org.hibernate.internal.util.StringHelper;
import org.hibernate.internal.util.collections.ArrayHelper;
import org.hibernate.param.DynamicFilterParameterSpecification;
import org.hibernate.sql.JoinFragment;
import org.hibernate.sql.JoinType;
import org.hibernate.type.Type;
/**
* 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 CoreMessageLogger LOG = CoreLogging.messageLogger( 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 JoinType toHibernateJoinType(int astJoinType) {
switch ( astJoinType ) {
case LEFT_OUTER: {
return JoinType.LEFT_OUTER_JOIN;
}
case INNER: {
return JoinType.INNER_JOIN;
}
case RIGHT_OUTER: {
return JoinType.RIGHT_OUTER_JOIN;
}
case FULL: {
return JoinType.FULL_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 = new ArrayList( fromClause.getFromElements().size() );
ListIterator<FromElement> liter = fromClause.getFromElements().listIterator();
while ( liter.hasNext() ) {
FromElement fromElement = liter.next();
// We found an implied from element that is used in the WITH clause of another from element, so it need to become part of it's join sequence
if ( fromElement instanceof ImpliedFromElement
&& fromElement.getOrigin().getWithClauseFragment() != null
&& fromElement.getOrigin().getWithClauseFragment().contains( fromElement.getTableAlias() ) ) {
fromElement.getOrigin().getJoinSequence().addJoin( (ImpliedFromElement) fromElement );
// This from element will be rendered as part of the origins join sequence
fromElement.setText("");
}
else {
fromElements.add( fromElement );
}
}
}
// 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.tracev(
"Forcing inclusion of extra joins [alias={0}, containsTableAlias={1}]",
alias,
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()
);
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() ||
( fromElement.getFromClause().isSubQuery()
&& fromElement.isDereferencedBySuperclassOrSubclassProperty() ) /*&& StringHelper.isNotEmpty( frag )*/ ) {
String fromFragment = processFromFragment( frag, join ).trim();
LOG.debugf( "Using FROM fragment [%s]", 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 = ParserHelper.HQL_SEPARATORS + dialect.openQuote() + dialect.closeQuote();
StringTokenizer tokens = new StringTokenizer( sqlFragment, symbols, true );
StringBuilder result = new StringBuilder();
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;
if ( value != null && Collection.class.isInstance( value ) ) {
bindFragment = StringHelper.join(
",",
ArrayHelper.fillArray( typeBindFragment, ( (Collection) value ).size() )
);
}
else {
bindFragment = 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.contains( ParserHelper.HQL_VARIABLE_PREFIX );
}
private static boolean hasCollectionFilterParam(String sqlFragment) {
return !sqlFragment.contains( "?" );
}
}