import org.jivesoftware.smackx.packet.DiscoverInfo.Feature; //导入依赖的package包/类
private boolean checkIfPrivacyIsSupported(XMPPConnection conn) {
    ServiceDiscoveryManager servDisc = ServiceDiscoveryManager.getInstanceFor(conn);
    DiscoverInfo info = null;
	//Re: SPARK-1483 comment the loop as it causes Out Of Memory (infinite loop) if info not found
	//If really necessary to try more times, a Thread Pool may be used: java ScheduledThreadPoolExecutor for example 
    //while (info == null){
        try {
        	String xmppHost = DNSUtil.resolveXMPPDomain(conn.getServiceName()).getHost();
            info = servDisc.discoverInfo(xmppHost);
        } catch (XMPPException e) {
        	// We could not query the server
        }
    //}
    if (info != null) {
        for (Iterator<Feature> i = info.getFeatures(); i.hasNext();) {
            String s = i.next().getVar();
            if (s.contains("jabber:iq:privacy")) {
                return true;
            }
        }
    } 
    return false;
}