001/**
002 *
003 * Copyright the original author or authors
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.jivesoftware.smackx.pubsub.packet;
018
019import org.jivesoftware.smack.packet.IQ;
020import org.jivesoftware.smack.packet.ExtensionElement;
021import org.jivesoftware.smackx.pubsub.PubSubElementType;
022import org.jxmpp.jid.Jid;
023
024/**
025 * The standard PubSub extension of an {@link IQ} packet.  This is the topmost
026 * element of all pubsub requests and replies as defined in the <a href="http://xmpp.org/extensions/xep-0060">Publish-Subscribe</a> 
027 * specification.
028 * 
029 * @author Robin Collier
030 */
031public class PubSub extends IQ
032{
033    public static final String ELEMENT = "pubsub";
034    public static final String NAMESPACE = "http://jabber.org/protocol/pubsub";
035
036    public PubSub() {
037        super(ELEMENT, NAMESPACE);
038    }
039
040    public PubSub(PubSubNamespace ns) {
041        super(ELEMENT, ns.getXmlns());
042    }
043
044    public PubSub(Jid to, Type type, PubSubNamespace ns) {
045        super(ELEMENT, (ns == null ? PubSubNamespace.BASIC : ns).getXmlns());
046        setTo(to);
047        setType(type);
048    }
049
050    @SuppressWarnings("unchecked")
051    public <PE extends ExtensionElement> PE getExtension(PubSubElementType elem)
052    {
053        return (PE) getExtension(elem.getElementName(), elem.getNamespace().getXmlns());
054    }
055
056    /**
057     * Returns the XML representation of a pubsub element according the specification.
058     * 
059     * The XML representation will be inside of an iq stanza(/packet) like
060     * in the following example:
061     * <pre>
062     * &lt;iq type='set' id="MlIpV-4" to="pubsub.gato.home" from="gato3@gato.home/Smack"&gt;
063     *     &lt;pubsub xmlns="http://jabber.org/protocol/pubsub"&gt;
064     *                      :
065     *         Specific request extension
066     *                      :
067     *     &lt;/pubsub&gt;
068     * &lt;/iq&gt;
069     * </pre>
070     * 
071     */
072    @Override
073    protected IQChildElementXmlStringBuilder getIQChildElementBuilder(IQChildElementXmlStringBuilder xml) {
074        // N.B. We could use SimpleIQ here, but PubSub IQs will nearly *always* have packet extensions, which means that
075        // SimpleIQs xml.setEmptyElement() is counter-productive in this case and we use xml.rightAngleBracket()
076        // instead, as there are likely sub-elements to follow.
077        xml.rightAngleBracket();
078        return xml;
079    }
080
081    public static PubSub createPubsubPacket(Jid to, Type type, ExtensionElement extension, PubSubNamespace ns) {
082        PubSub pubSub = new PubSub(to, type, ns);
083        pubSub.addExtension(extension);
084        return pubSub;
085    }
086}