/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 * 
 * Portions Copyright Apache Software Foundation.
 * 
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
 * as provided by Sun in the GPL Version 2 section of the License file that
 * accompanied this code.  If applicable, add the following below the License
 * Header, with the fields enclosed by brackets [] replaced by your own
 * identifying information: "Portions Copyrighted [year]
 * [name of copyright owner]"
 * 
 * Contributor(s):
 * 
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package org.apache.taglibs.standard.extra.spath;

import java.util.List;
import java.util.Vector;

/**
 * <p>Represents a relative SPath expression.</p>
 *
 * @author Shawn Bayern
 */
public class RelativePath extends Path {

    private RelativePath next;
    private Step step;

    /**
     * Constructs a new RelativePath object, based on a Step and another
     * (possibly null) RelativePath.  If 'all' is true, then the path
     * matches all instances of 'next' underneath 'step'; otherwise;
     * 'next' must be an immediate child of 'step'.
     */
    public RelativePath(Step step, RelativePath next) {
	if (step == null)
	    throw new IllegalArgumentException("non-null step required");
	this.step = step;
	this.next = next;
    }

    // inherit JavaDoc comment
    public List getSteps() {
	// simply merge our 'step' with our 'next'
	List l;
	if (next != null)
	    l = next.getSteps();
	else
	    l = new Vector();
	l.add(0, step);
	return l;
    }
}