org.eclipse.persistence.internal.jpa.parsing.OrderByNode Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation

EclipseLink build based upon Git transaction f2b9fc5

There is a newer version: 5.0.0-B03

/*
 * Copyright (c) 1998, 2021 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 from Oracle TopLink
package org.eclipse.persistence.internal.jpa.parsing;

import java.util.*;

import org.eclipse.persistence.queries.ObjectLevelReadQuery;

/**
 * INTERNAL
 * Purpose: Represent an ORDER BY
 * 
Responsibilities:

 *  Generate the correct expression for an ORDER BY
 * 
 *    @author Jon Driscoll
 *    @since TopLink 5.0
 */
public class OrderByNode extends MajorNode {

    List orderByItems = null;

    /**
     * Return a new OrderByNode.
     */
    public OrderByNode() {
        super();
    }

    /**
     * INTERNAL
     * Add the ordering expressions to the passed query
     */
    public void addOrderingToQuery(ObjectLevelReadQuery theQuery, GenerationContext context) {
        if (theQuery.isReadAllQuery()) {
            Iterator iter = getOrderByItems().iterator();
            while (iter.hasNext()) {
                Node nextNode = iter.next();
                theQuery.addOrdering(nextNode.generateExpression(context));
            }
        }
    }

    /**
     * INTERNAL
     * Validate node.
     */
    public void validate(ParseTreeContext context, SelectNode selectNode) {
        for (Iterator i = orderByItems.iterator(); i.hasNext(); ) {
            Node item = i.next();
            item.validate(context);
        }
    }

    /**
     * INTERNAL
     * Return the order by statements
     */
    public List getOrderByItems() {
        if (orderByItems == null) {
            setOrderByItems(new Vector<>());
        }
        return orderByItems;
    }

    /**
     * INTERNAL
     * Set the order by statements
     */
    public void setOrderByItems(List newItems) {
        orderByItems = newItems;
    }
}