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EclipseLink build based upon Git transaction ecdf3c32c4
/*
* Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Oracle - initial API and implementation
//
package org.eclipse.persistence.internal.jpa.jpql;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.eclipse.persistence.expressions.Expression;
import org.eclipse.persistence.jpa.jpql.parser.CollectionExpression;
import org.eclipse.persistence.jpa.jpql.parser.EclipseLinkAnonymousExpressionVisitor;
import org.eclipse.persistence.jpa.jpql.parser.HierarchicalQueryClause;
import org.eclipse.persistence.jpa.jpql.parser.OrderSiblingsByClause;
import org.eclipse.persistence.queries.ReadAllQuery;
/**
* This visitor is responsible to populate a {@link ReadAllQuery}.
*
* @version 2.5
* @since 2.5
* @author Pascal Filion
*/
class ReadAllQueryVisitor extends AbstractObjectLevelReadQueryVisitor {
/**
* Creates a new ReadAllQueryVisitor
.
*
* @param queryContext The context used to query information about the application metadata and
* cached information
* @param query The {@link ReportQuery} to populate by using this visitor to visit the parsed
* tree representation of the JPQL query
*/
ReadAllQueryVisitor(JPQLQueryContext queryContext, ReadAllQuery query) {
super(queryContext, query);
}
/**
* {@inheritDoc}
*/
@Override
public void visit(HierarchicalQueryClause expression) {
// START WITH clause
Expression startWithClause = null;
if (expression.hasStartWithClause()) {
startWithClause = queryContext.buildExpression(expression.getStartWithClause());
}
// CONNECT BY clause
Expression connectByClause = queryContext.buildExpression(expression.getConnectByClause());
// ORDER SIBLINGS BY clause
List orderItems = Collections.emptyList();
if (expression.hasOrderSiblingsByClause()) {
OrderSiblingsByClauseVisitor visitor = new OrderSiblingsByClauseVisitor();
expression.getOrderSiblingsByClause().accept(visitor);
orderItems = visitor.orderByItems;
}
// Now add the hierarchical query clause
ReadAllQuery query = (ReadAllQuery) this.query;
query.setHierarchicalQueryClause(startWithClause, connectByClause, orderItems);
}
private class OrderSiblingsByClauseVisitor extends EclipseLinkAnonymousExpressionVisitor {
/**
* The ordered list of items.
*/
List orderByItems;
/**
* Creates a new OrderSiblingsByClauseVisitor
.
*/
OrderSiblingsByClauseVisitor() {
super();
orderByItems = new ArrayList();
}
/**
* {@inheritDoc}
*/
@Override
public void visit(CollectionExpression expression) {
expression.acceptChildren(this);
}
/**
* {@inheritDoc}
*/
@Override
public void visit(OrderSiblingsByClause expression) {
expression.getOrderByItems().accept(this);
}
/**
* {@inheritDoc}
*/
@Override
public void visit(org.eclipse.persistence.jpa.jpql.parser.Expression expression) {
orderByItems.add(queryContext.buildExpression(expression));
}
}
}