ParserManager.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.io.InputStream;
import java.util.Enumeration;
import java.util.Map;
import java.util.Properties;
import java.util.concurrent.ConcurrentHashMap;

import org.dom4j.Document;
import org.dom4j.Element;
import org.olat.core.logging.OLATRuntimeException;
import org.olat.core.logging.OLog;
import org.olat.core.logging.Tracing;

/**
 * @author rkulow
 */
public class ParserManager implements IParser {
	private static final OLog log = Tracing.createLoggerFor(ParserManager.class);
	private static String PROPERTIES_FILENAME = "org/olat/ims/qti/editor/beecom/parser/qtiparser.properties";
	private static final Map<String,String> parserMap = new ConcurrentHashMap<>();
	private static String PARSER_DEFAULT = "defaultparser";

	public ParserManager() {
		init();
	}

	private void init() {
		if(parserMap.isEmpty()) {
			try(InputStream in = this.getClass().getClassLoader().getResourceAsStream(PROPERTIES_FILENAME)) {
				Properties prop = new Properties();
				prop.load(in);
				for(Enumeration<Object> enumeration = prop.keys(); enumeration.hasMoreElements(); ) {
					String key = (String) enumeration.nextElement();
					String value = prop.getProperty(key);
					parserMap.put(key, value);
				}
			} catch (Exception e) {
				log.error("Could not load qtiparser.properties", e);
			}
		}
	}

	/**
	 * @param doc
	 * @return
	 */
	public Object parse(Document doc) {
		Element rootElement = doc.getRootElement();
		return parse(rootElement);
	}

	/**
	 * @see org.olat.ims.qti.editor.beecom.parser.IParser#parse(org.dom4j.Element)
	 */
	public Object parse(Element element) {
		try {
			if (element == null) return null;
			String name = element.getName();
			String parserClassName = null;
			String tmpName = parserMap.get(name);
			if (tmpName == null) {
				parserClassName = parserMap.get(PARSER_DEFAULT);
			} else {
				parserClassName = tmpName;
			}
			if(log.isDebug()){
				log.debug("ELEMENTNAME:" + name + "PARSERNAME" + parserClassName);
			}
			Class<?> parserClass = this.getClass().getClassLoader().loadClass(parserClassName);
			IParser parser = (IParser) parserClass.newInstance();
			return parser.parse(element);
		} catch (ClassNotFoundException e) {
			throw new OLATRuntimeException(this.getClass(), "Class not found in QTI editor", e);
		} catch (InstantiationException e) {
			throw new OLATRuntimeException(this.getClass(), "Instatiation problem in QTI editor", e);
		} catch (IllegalAccessException e) {
			throw new OLATRuntimeException(this.getClass(), "Illegal Access in QTI editor", e);
		}
	}
}