/** * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.jivesoftware.smack.provider; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.jivesoftware.smack.packet.PacketExtension; import org.jivesoftware.smack.provider.PacketExtensionProvider; import org.jivesoftware.smack.util.PacketParserUtils; import org.jivesoftware.smackx.pubsub.provider.ItemProvider; import org.jivesoftware.smackx.pubsub.provider.ItemsProvider; import org.xmlpull.v1.XmlPullParser; /** * * This class simplifies parsing of embedded elements by using the * Template Method Pattern. * After extracting the current element attributes and content of any child elements, the template method * ({@link #createReturnExtension(String, String, Map, List)} is called. Subclasses * then override this method to create the specific return type. * *

To use this class, you simply register your subclasses as extension providers in the * smack.properties file. Then they will be automatically picked up and used to parse * any child elements. * *

 * For example, given the following message
 * 
 * <message from='pubsub.shakespeare.lit' to='francisco@denmark.lit' id='foo>
 *    <event xmlns='http://jabber.org/protocol/pubsub#event>
 *       <items node='princely_musings'>
 *          <item id='asdjkwei3i34234n356'>
 *             <entry xmlns='http://www.w3.org/2005/Atom'>
 *                <title>Soliloquy</title>
 *                <link rel='alternative' type='text/html'/>
 *                <id>tag:denmark.lit,2003:entry-32397</id>
 *             </entry>
 *          </item>
 *       </items>
 *    </event>
 * </message>
 * 
 * I would have a classes
 * {@link ItemsProvider} extends {@link EmbeddedExtensionProvider}
 * {@link ItemProvider} extends {@link EmbeddedExtensionProvider}
 * and
 * AtomProvider extends {@link PacketExtensionProvider}
 * 
 * These classes are then registered in the meta-inf/smack.providers file
 * as follows.
 * 
 *   <extensionProvider>
 *      <elementName>items</elementName>
 *      <namespace>http://jabber.org/protocol/pubsub#event</namespace>
 *      <className>org.jivesoftware.smackx.provider.ItemsEventProvider</className>
 *   </extensionProvider>
 *   <extensionProvider>
 *       <elementName>item</elementName>
 *       <namespace>http://jabber.org/protocol/pubsub#event</namespace>
 *       <className>org.jivesoftware.smackx.provider.ItemProvider</className>
 *   </extensionProvider>
 * 
 * 
* * @author Robin Collier */ abstract public class EmbeddedExtensionProvider implements PacketExtensionProvider { final public PacketExtension parseExtension(XmlPullParser parser) throws Exception { String namespace = parser.getNamespace(); String name = parser.getName(); Map attMap = new HashMap(); for(int i=0; i extensions = new ArrayList(); do { int tag = parser.next(); if (tag == XmlPullParser.START_TAG) extensions.add(PacketParserUtils.parsePacketExtension(parser.getName(), parser.getNamespace(), parser)); } while (!name.equals(parser.getName())); return createReturnExtension(name, namespace, attMap, extensions); } abstract protected PacketExtension createReturnExtension(String currentElement, String currentNamespace, Map attributeMap, List content); }