/*
* 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.query.criteria.internal.path;
import java.io.Serializable;
import javax.persistence.criteria.Expression;
import javax.persistence.criteria.From;
import javax.persistence.criteria.JoinType;
import javax.persistence.criteria.Predicate;
import javax.persistence.metamodel.Attribute;
import org.hibernate.query.criteria.internal.CriteriaBuilderImpl;
import org.hibernate.query.criteria.internal.CriteriaSubqueryImpl;
import org.hibernate.query.criteria.internal.FromImplementor;
import org.hibernate.query.criteria.internal.JoinImplementor;
import org.hibernate.query.criteria.internal.PathSource;
import org.hibernate.query.criteria.internal.compile.RenderingContext;
import org.hibernate.query.criteria.internal.predicate.AbstractPredicateImpl;
/**
* Convenience base class for various {@link javax.persistence.criteria.Join} implementations.
*
* @author Steve Ebersole
*/
public abstract class AbstractJoinImpl<Z, X>
extends AbstractFromImpl<Z, X>
implements JoinImplementor<Z,X>, Serializable {
private final Attribute<? super Z, ?> joinAttribute;
private final JoinType joinType;
private Predicate suppliedJoinCondition;
public AbstractJoinImpl(
CriteriaBuilderImpl criteriaBuilder,
PathSource<Z> pathSource,
Attribute<? super Z, X> joinAttribute,
JoinType joinType) {
this( criteriaBuilder, joinAttribute.getJavaType(), pathSource, joinAttribute, joinType );
}
public AbstractJoinImpl(
CriteriaBuilderImpl criteriaBuilder,
Class<X> javaType,
PathSource<Z> pathSource,
Attribute<? super Z, ?> joinAttribute,
JoinType joinType) {
super( criteriaBuilder, javaType, pathSource );
this.joinAttribute = joinAttribute;
this.joinType = joinType;
}
@Override
public Attribute<? super Z, ?> getAttribute() {
return joinAttribute;
}
@Override
public JoinType getJoinType() {
return joinType;
}
@Override
@SuppressWarnings({ "unchecked" })
public From<?, Z> getParent() {
// this cast should be ok by virtue of our constructors...
return (From<?, Z>) getPathSource();
}
@Override
public String renderTableExpression(RenderingContext renderingContext) {
prepareAlias( renderingContext );
( (FromImplementor) getParent() ).prepareAlias( renderingContext );
StringBuilder tableExpression = new StringBuilder();
tableExpression.append( getParent().getAlias() )
.append( '.' )
.append( getAttribute().getName() )
.append( " as " )
.append( getAlias() );
if ( suppliedJoinCondition != null ) {
tableExpression.append( " with " )
.append( ( (AbstractPredicateImpl) suppliedJoinCondition ).render( renderingContext ) );
}
return tableExpression.toString();
}
@Override
public JoinImplementor<Z, X> correlateTo(CriteriaSubqueryImpl subquery) {
return (JoinImplementor<Z, X>) super.correlateTo( subquery );
}
@Override
public JoinImplementor<Z, X> on(Predicate... restrictions) {
// no matter what, a call to this method replaces any previously set values...
this.suppliedJoinCondition = null;
if ( restrictions != null && restrictions.length > 0 ) {
this.suppliedJoinCondition = criteriaBuilder().and( restrictions );
}
return this;
}
@Override
public JoinImplementor<Z, X> on(Expression<Boolean> restriction) {
this.suppliedJoinCondition = criteriaBuilder().wrap( restriction );
return this;
}
@Override
public Predicate getOn() {
return suppliedJoinCondition;
}
}