OF 同步异步问题的改进

之前的一篇文章中提到过OF中的同步异步问题，这里针对文章最后描述的两个缺点做些改进。

这里提供一个公共的专门用于处理S2S通信问题的IQ类S2SDataManager。

可以提供多种接口：1.阻塞等待固定时长；2.阻塞等待，并在接收到结果或超时后继续；3.发送后直接返回；4.发送后直接返回，提供回调接口。

public class S2SDataManager implements IQResultListener{
private XMPPServer server;
private RoutingTable routing;
private long timeout=3000;  //3 秒超时
//用来存储接收到的S2S结果包
private Map<String,Packet> results = new ConcurrentHashMap<String,Packet>();
//用来存储同步锁
private Map<String,Notifyer> noties = new ConcurrentHashMap<String,Notifyer>();
//用来存储回调接口实现类对象
private Map<String,S2SIQResultListener> liteners = new ConcurrentHashMap<String,S2SIQResultListener>();
//用来存储超时处理对象
private Map<String,Long> gards = new ConcurrentHashMap<String,Long>();

private static class S2SDataManagerContainer{
private static S2SDataManager instance = new S2SDataManager();
}

public static S2SDataManager getInstance(){
return S2SDataManagerContainer.instance;
}

private S2SDataManager(){
//一些初始化
}

//方法1
public Packet send(Packet packet,int time){
//类似于OF中原有的方法
}

//方法2
public Packet send(Packet packet){
String id = packet.getID();
Notifyer noty = new Notifyer(id);
noties.put(id,noty);
addIQRouterListener(id);
synchronized(noty){
routing.routePacket(packet.getTo(),packet.true);
try{
noty.wait(timeout);
}
catch(InterruptedException ex){
//log it
}
}
Packet reply =results.remove(packet.getID());
return reply;
}

@override
public void receivedAnswer(IQ iq){
this.results.put(iq.getID(),iq);
Notifyer noty = noties.remove(iq.getID());
if(noty!=null){
synchronized(noty){
try{
noty.notify();
}
catch(Exception ex){
//log it
}
}
}
}

//方法3
public void send(Packet packet){
routing.routePacket(Packet.getTo(),packet,true);
}

//方法4
public void send(Packet packet,S2SIQResultListener listener){
String id = packet.getID();
addIQRouterListener(id);
listeners.put(id,listener);
gards.put(id,System.currentTimeMillis()+timeout);
routing.routePacket(packet.getTo(),packet,true);
}

@Override
public void answerTimeout(String id){
//外部超时通知处理
}

private class TimeOutTask extends TimerTask{

@Override
public void run(){
final Iterator<Map.Entry<String,Long> it = gards.entitySet().iterator();
while(it.hasNext){
final Map.Entry<String,Long> point= it.next();
if(System.currentTimeMillis()<point.getValue()){
continue;
}
listeners.remove(point.getKey());
it.remove();
}
}

}

}