/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2009 by Red Hat Inc and/or its affiliates or by
* third-party contributors as indicated by either @author tags or express
* copyright attribution statements applied by the authors. All
* third-party contributions are distributed under license by Red Hat Inc.
*
* 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.ejb.criteria.predicate;
import java.io.Serializable;
import java.util.Collection;
import org.hibernate.ejb.criteria.CriteriaBuilderImpl;
import org.hibernate.ejb.criteria.CriteriaQueryCompiler;
import org.hibernate.ejb.criteria.ParameterRegistry;
import org.hibernate.ejb.criteria.expression.UnaryOperatorExpression;
import org.hibernate.ejb.criteria.path.PluralAttributePath;
/**
* Models an <tt>IS [NOT] EMPTY</tt> restriction
*
* @author Steve Ebersole
*/
public class IsEmptyPredicate<C extends Collection>
extends AbstractSimplePredicate
implements UnaryOperatorExpression<Boolean>, Serializable {
private final PluralAttributePath<C> collectionPath;
public IsEmptyPredicate(
CriteriaBuilderImpl criteriaBuilder,
PluralAttributePath<C> collectionPath) {
super( criteriaBuilder );
this.collectionPath = collectionPath;
}
public PluralAttributePath<C> getOperand() {
return collectionPath;
}
public void registerParameters(ParameterRegistry registry) {
// nothing to do
}
public String render(CriteriaQueryCompiler.RenderingContext renderingContext) {
final String operator = isNegated() ? " is not empty" : " is empty";
return getOperand().render( renderingContext ) + operator;
}
public String renderProjection(CriteriaQueryCompiler.RenderingContext renderingContext) {
return render( renderingContext );
}
}