google cloud messaging - GCM XMPP Server using Smack 4.1.0

Question

I'm trying to adapt the example provided here for Smack 4.1.0. and getting a little confused.

Specifically I'm struggling to understand what the GcmPacketExtension should now extend, how the constructor should work and how the Providermanager.addExtensionProvider should be updated to tie in with it.

I'm sure someone must have done this before but I can't find any examples and I seem to be going round in circles using just the documentation.

Any help would be much appreciated, I'm sure the answer is very simple!

Current Code (is compiling but not running):

    static {

    ProviderManager.addExtensionProvider(GCM_ELEMENT_NAME, GCM_NAMESPACE, new  ExtensionElementProvider<ExtensionElement>() {
        @Override
        public DefaultExtensionElement parse(XmlPullParser parser,int initialDepth) throws org.xmlpull.v1.XmlPullParserException,
        IOException {
            String json = parser.nextText();
            return new GcmPacketExtension(json);
        }
    });
}

and:

private static final class GcmPacketExtension extends DefaultExtensionElement   {

    private final String json;

    public GcmPacketExtension(String json) {
        super(GCM_ELEMENT_NAME, GCM_NAMESPACE);
        this.json = json;
    }

    public String getJson() {
        return json;
    }

    @Override
    public String toXML() {
        return String.format("<%s xmlns="%s">%s</%s>",
                GCM_ELEMENT_NAME, GCM_NAMESPACE,
                StringUtils.escapeForXML(json), GCM_ELEMENT_NAME);
    }

    public Stanza toPacket() {
        Message message = new Message();
        message.addExtension(this);
        return message;
    }
}

Current exception:

Exception in thread "main" java.lang.NoClassDefFoundError: de/measite/minidns/DNSCache
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.jivesoftware.smack.SmackInitialization.loadSmackClass(SmackInitialization.java:213)
at org.jivesoftware.smack.SmackInitialization.parseClassesToLoad(SmackInitialization.java:193)
at org.jivesoftware.smack.SmackInitialization.processConfigFile(SmackInitialization.java:163)
at org.jivesoftware.smack.SmackInitialization.processConfigFile(SmackInitialization.java:148)
at org.jivesoftware.smack.SmackInitialization.<clinit>(SmackInitialization.java:116)
at org.jivesoftware.smack.SmackConfiguration.getVersion(SmackConfiguration.java:96)
at org.jivesoftware.smack.provider.ProviderManager.<clinit>(ProviderManager.java:121)
at SmackCcsClient.<clinit>(SmackCcsClient.java:58)
Caused by: java.lang.ClassNotFoundException: de.measite.minidns.DNSCache
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 10 more

Answer 1

Waitting for answers