org.jivesoftware.smack.provider

Class EmbeddedExtensionProvider

java.lang.Object

org.jivesoftware.smack.provider.EmbeddedExtensionProvider

All Implemented Interfaces:

PacketExtensionProvider

Direct Known Subclasses:

AffiliationProvider, AffiliationsProvider, ConfigEventProvider, DeliveryReceipt.Provider, EventProvider, FormNodeProvider, HeadersProvider, ItemsProvider, RetractEventProvider, SimpleNodeProvider, SubscriptionsProvider

public abstract class EmbeddedExtensionProvider
extends Object
implements PacketExtensionProvider

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 (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
 ItemsProvider extends EmbeddedExtensionProvider
 ItemProvider extends EmbeddedExtensionProvider
 and
 AtomProvider extends 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>
 
 

Constructor Summary

Constructors

Constructor and Description
EmbeddedExtensionProvider()

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract PacketExtension	createReturnExtension(String currentElement, String currentNamespace, Map<String,String> attributeMap, List<? extends PacketExtension> content)
PacketExtension	parseExtension(org.xmlpull.v1.XmlPullParser parser) Parse an extension sub-packet and create a PacketExtension instance.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

EmbeddedExtensionProvider

public EmbeddedExtensionProvider()

Method Detail

parseExtension

public final PacketExtension parseExtension(org.xmlpull.v1.XmlPullParser parser)
                                     throws Exception

Description copied from interface: PacketExtensionProvider

Parse an extension sub-packet and create a PacketExtension instance. At the beginning of the method call, the xml parser will be positioned on the opening element of the packet extension. At the end of the method call, the parser must be positioned on the closing element of the packet extension.

Specified by:

parseExtension in interface PacketExtensionProvider

Parameters:

parser - an XML parser.

Returns:

a new IQ instance.

Throws:

Exception - if an error occurs parsing the XML.

createReturnExtension

protected abstract PacketExtension createReturnExtension(String currentElement,
                                    String currentNamespace,
                                    Map<String,String> attributeMap,
                                    List<? extends PacketExtension> content)