SelectionOrderingParser.java

/**
* OLAT - Online Learning and Training<br>
* http://www.olat.org
* <p>
* Licensed under the Apache License, Version 2.0 (the "License"); <br>
* you may not use this file except in compliance with the License.<br>
* You may obtain a copy of the License at
* <p>
* http://www.apache.org/licenses/LICENSE-2.0
* <p>
* Unless required by applicable law or agreed to in writing,<br>
* software distributed under the License is distributed on an "AS IS" BASIS, <br>
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. <br>
* See the License for the specific language governing permissions and <br>
* limitations under the License.
* <p>
* Copyright (c) since 2004 at Multimedia- & E-Learning Services (MELS),<br>
* University of Zurich, Switzerland.
* <hr>
* <a href="http://www.openolat.org">
* OpenOLAT - Online Learning and Training</a><br>
* This file has been modified by the OpenOLAT community. Changes are licensed
* under the Apache 2.0 license as the original file.
*/

package org.olat.ims.qti.editor.beecom.parser;

import java.util.List;

import org.dom4j.Element;
import org.olat.core.logging.OLATRuntimeException;
import org.olat.ims.qti.editor.beecom.objects.SelectionOrdering;

/**
 * Initial Date:  Sep 23, 2003
 *
 * @author gnaegi<br>
 * 
 * Comment: Parser for the selection_ordering elements (at section level).
 * Uses the number of choosen items from the selection_number element if available
 * and the ordering type from the order element. Uses default values from the 
 * SelectionOrdering class in cases of non exising elements
 * </pre>
 */
public class SelectionOrderingParser implements IParser {
	
	/**
	 * @see org.olat.ims.qti.editor.beecom.IParser#parse(org.dom4j.Element)
	 */
	public Object parse(Element element) {
		//assert element.getName().equalsIgnoreCase("selection_ordering");
					
		SelectionOrdering selectionOrdering = new SelectionOrdering();

		// Set correct selection of items. To select all is the default value (represented
		// by a non existing 'selection_number' element. Otherwhise the exact number given
		// in the 'selection_number' element is taken')
		List el_selections = element.selectNodes("selection");
		if(el_selections.size()>1){
			//error
			throw new OLATRuntimeException(SelectionOrderingParser.class, "more then one selection element", new IllegalStateException());
		}
		if (el_selections.size() != 0){
			Element el_selection = ((Element)el_selections.get(0));
			Element selection_number = (Element)el_selection.selectSingleNode("selection_number");
			if (selection_number != null) {
				selectionOrdering.setSelectionNumber(Integer.parseInt(selection_number.getText()));
			}
		} 
		// else use default value
		
		// Set correct order type. Use sequential ordering als default if none defined
		Element order = (Element)element.selectSingleNode("order");
		if (order != null) {
			String order_type = order.attributeValue(SelectionOrdering.ORDER_TYPE);
			if (order_type != null && order_type.equals(SelectionOrdering.RANDOM)) {
				selectionOrdering.setOrderType(SelectionOrdering.RANDOM); 
			}
			// else use default value
		} 

		return selectionOrdering;
	}
}