@Override
    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
        authenticated = ExternalizableUtil.getInstance().readBoolean(in);
    }
Task that will be executed in cluster nodes to get the number of sessions hosted by the
cluster node.

@author Gaston Dombiak
xmppserver/src/main/java/org/jivesoftware/openfire/session/GetSessionsCountTask.java