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();
            }
        }

    }

 }