/*
* 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;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import javax.persistence.Tuple;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Expression;
import javax.persistence.criteria.Order;
import javax.persistence.criteria.ParameterExpression;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;
import javax.persistence.criteria.Selection;
import javax.persistence.criteria.Subquery;
import javax.persistence.metamodel.EntityType;
import org.hibernate.ejb.HibernateEntityManagerImplementor;
import org.hibernate.type.Type;
/**
* The Hibernate implementation of the JPA {@link CriteriaQuery} contract. Mostly a set of delegation to its
* internal {@link QueryStructure}.
*
* @author Steve Ebersole
*/
public class CriteriaQueryImpl<T> extends AbstractNode implements CriteriaQuery<T>, Serializable {
private final Class<T> returnType;
private final QueryStructure<T> queryStructure;
private List<Order> orderSpecs = Collections.emptyList();
public CriteriaQueryImpl(
CriteriaBuilderImpl criteriaBuilder,
Class<T> returnType) {
super( criteriaBuilder );
this.returnType = returnType;
this.queryStructure = new QueryStructure<T>( this, criteriaBuilder );
}
/**
* {@inheritDoc}
*/
public Class<T> getResultType() {
return returnType;
}
// SELECTION ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> distinct(boolean applyDistinction) {
queryStructure.setDistinct( applyDistinction );
return this;
}
/**
* {@inheritDoc}
*/
public boolean isDistinct() {
return queryStructure.isDistinct();
}
/**
* {@inheritDoc}
*/
@SuppressWarnings({ "unchecked" })
public Selection<T> getSelection() {
return ( Selection<T> ) queryStructure.getSelection();
}
public void applySelection(Selection<? extends T> selection) {
queryStructure.setSelection( selection );
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> select(Selection<? extends T> selection) {
applySelection( selection );
return this;
}
/**
* {@inheritDoc}
*/
@SuppressWarnings({ "unchecked" })
public CriteriaQuery<T> multiselect(Selection<?>... selections) {
return multiselect( Arrays.asList( selections ) );
}
/**
* {@inheritDoc}
*/
@SuppressWarnings({ "unchecked" })
public CriteriaQuery<T> multiselect(List<Selection<?>> selections) {
final Selection<? extends T> selection;
if ( Tuple.class.isAssignableFrom( getResultType() ) ) {
selection = ( Selection<? extends T> ) criteriaBuilder().tuple( selections );
}
else if ( getResultType().isArray() ) {
selection = ( Selection<? extends T> ) criteriaBuilder().array(
( Class<? extends Object[]> ) getResultType(),
selections
);
}
else if ( Object.class.equals( getResultType() ) ) {
switch ( selections.size() ) {
case 0: {
throw new IllegalArgumentException(
"empty selections passed to criteria query typed as Object"
);
}
case 1: {
selection = ( Selection<? extends T> ) selections.get( 0 );
break;
}
default: {
selection = ( Selection<? extends T> ) criteriaBuilder().array( selections );
}
}
}
else {
selection = criteriaBuilder().construct( getResultType(), selections );
}
applySelection( selection );
return this;
}
// ROOTS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* {@inheritDoc}
*/
public Set<Root<?>> getRoots() {
return queryStructure.getRoots();
}
/**
* {@inheritDoc}
*/
public <X> Root<X> from(EntityType<X> entityType) {
return queryStructure.from( entityType );
}
/**
* {@inheritDoc}
*/
public <X> Root<X> from(Class<X> entityClass) {
return queryStructure.from( entityClass );
}
// RESTRICTION ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* {@inheritDoc}
*/
public Predicate getRestriction() {
return queryStructure.getRestriction();
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> where(Expression<Boolean> expression) {
queryStructure.setRestriction( criteriaBuilder().wrap( expression ) );
return this;
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> where(Predicate... predicates) {
// TODO : assuming this should be a conjuntion, but the spec does not say specifically...
queryStructure.setRestriction( criteriaBuilder().and( predicates ) );
return this;
}
// GROUPING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* {@inheritDoc}
*/
public List<Expression<?>> getGroupList() {
return queryStructure.getGroupings();
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> groupBy(Expression<?>... groupings) {
queryStructure.setGroupings( groupings );
return this;
}
public CriteriaQuery<T> groupBy(List<Expression<?>> groupings) {
queryStructure.setGroupings( groupings );
return this;
}
/**
* {@inheritDoc}
*/
public Predicate getGroupRestriction() {
return queryStructure.getHaving();
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> having(Expression<Boolean> expression) {
queryStructure.setHaving( criteriaBuilder().wrap( expression ) );
return this;
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> having(Predicate... predicates) {
queryStructure.setHaving( criteriaBuilder().and( predicates ) );
return this;
}
// ORDERING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* {@inheritDoc}
*/
public List<Order> getOrderList() {
return orderSpecs;
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> orderBy(Order... orders) {
if ( orders != null && orders.length > 0 ) {
orderSpecs = Arrays.asList( orders );
}
else {
orderSpecs = Collections.emptyList();
}
return this;
}
/**
* {@inheritDoc}
*/
public CriteriaQuery<T> orderBy(List<Order> orders) {
orderSpecs = orders;
return this;
}
/**
* {@inheritDoc}
*/
public Set<ParameterExpression<?>> getParameters() {
return queryStructure.getParameters();
}
/**
* {@inheritDoc}
*/
public <U> Subquery<U> subquery(Class<U> subqueryType) {
return queryStructure.subquery( subqueryType );
}
public void validate() {
// getRoots() is explicitly supposed to return empty if none defined, no need to check for null
if ( getRoots().isEmpty() ) {
throw new IllegalStateException( "No criteria query roots were specified" );
}
// if there is not an explicit selection, there is an *implicit* selection of the root entity provided only
// a single query root was defined.
if ( getSelection() == null && !hasImplicitSelection() ) {
throw new IllegalStateException( "No explicit selection and an implicit one cold not be determined" );
}
}
/**
* If no explicit selection was defined, we have a condition called an implicit selection if the query specified
* a single {@link Root} and the java type of that {@link Root root's} model is the same as this criteria's
* {@link #getResultType() result type}.
*
* @return True if there is an explicit selection; false otherwise.
*/
private boolean hasImplicitSelection() {
if ( getRoots().size() != 1 ) {
return false;
}
Root root = getRoots().iterator().next();
if ( root.getModel().getJavaType() != returnType ) {
return false;
}
// if we get here, the query defined no selection but defined a single root of the same type as the
// criteria query return, so we use that as the implicit selection
//
// todo : should we put an implicit marker in the selection to this fact to make later processing easier?
return true;
}
public CriteriaQueryCompiler.RenderedCriteriaQuery render(CriteriaQueryCompiler.RenderingContext renderingContext) {
final StringBuilder jpaqlQuery = new StringBuilder();
queryStructure.render( jpaqlQuery, renderingContext );
if ( ! getOrderList().isEmpty() ) {
jpaqlQuery.append( " order by " );
String sep = "";
for ( Order orderSpec : getOrderList() ) {
jpaqlQuery.append( sep )
.append( ( ( Renderable ) orderSpec.getExpression() ).render( renderingContext ) )
.append( orderSpec.isAscending() ? " asc" : " desc" );
sep = ", ";
}
}
return new CriteriaQueryCompiler.RenderedCriteriaQuery() {
public String getQueryString() {
return jpaqlQuery.toString();
}
@SuppressWarnings({ "unchecked" })
public List<ValueHandlerFactory.ValueHandler> getValueHandlers() {
SelectionImplementor selection = (SelectionImplementor) queryStructure.getSelection();
return selection == null
? null
: selection.getValueHandlers();
}
public HibernateEntityManagerImplementor.Options.ResultMetadataValidator getResultMetadataValidator() {
return new HibernateEntityManagerImplementor.Options.ResultMetadataValidator() {
public void validate(Type[] returnTypes) {
SelectionImplementor selection = (SelectionImplementor) queryStructure.getSelection();
if ( selection != null ) {
if ( selection.isCompoundSelection() ) {
if ( returnTypes.length != selection.getCompoundSelectionItems().size() ) {
throw new IllegalStateException(
"Number of return values [" + returnTypes.length +
"] did not match expected [" +
selection.getCompoundSelectionItems().size() + "]"
);
}
}
else {
if ( returnTypes.length > 1 ) {
throw new IllegalStateException(
"Number of return values [" + returnTypes.length +
"] did not match expected [1]"
);
}
}
}
}
};
}
};
}
}