jxta通信程序，不知道为什么不好使。

服务端：
package primecruncher;

import net.jxta.peergroup.PeerGroup;
import net.jxta.peergroup.PeerGroupFactory;
import net.jxta.endpoint.MessageElement;
import net.jxta.discovery.DiscoveryService;
import net.jxta.pipe.PipeID;
import net.jxta.exception.PeerGroupException;
import net.jxta.protocol.PipeAdvertisement;
import net.jxta.document.*;
import net.jxta.id.IDFactory;
import net.jxta.pipe.PipeService;
import net.jxta.endpoint.Message;
import java.io.FileInputStream;
import net.jxta.util.JxtaServerPipe;
import net.jxta.util.JxtaBiDiPipe;
import net.jxta.endpoint.StringMessageElement;
import java.io.IOException;
import java.io.FileOutputStream;
import net.jxta.pipe.PipeMsgListener;
import net.jxta.pipe.PipeMsgEvent;
public class PrimePeer implements PipeMsgListener {
     private PipeAdvertisement pipeAdv;
     private JxtaServerPipe serverPipe;
     private final static String SenderMessage = "pipe_tutorial";
     private static PeerGroup group;
     private static DiscoveryService discoSvc;
     private static final String PIPE_ADV_FILE = "primeserver_pipe.adv";
     private final static String ReturnCred = "Authentication credential ";
     private final static String peerGroupID = "peer group ID ";
     private final static String peerID = "peer ID ";
     private  JxtaBiDiPipe bipipe;
     private String xiaoxi;
     private  PipeService pipeSvc;
        public static void main(String[] args) {

               PrimePeer pp = new PrimePeer();

               pp.startJxta();

               pp.doAdvertise();

        }

        public PrimePeer() {

        }

//初始化
        private void startJxta()
        {

               try {

                       group = PeerGroupFactory.newNetPeerGroup();//获取GROUP引用

                       discoSvc = group.getDiscoveryService();
                      
                       pipeSvc = group.getPipeService();
                      

               } catch (PeerGroupException e) {

                       System.out.println("Cannot create Net Peer Group: " + e.getMessage(

));

                       System.exit(-1);

               }
        }
     
//创建广告并发布
        private void doAdvertise() {   
         try {
            FileInputStream is = new FileInputStream(PIPE_ADV_FILE);
            pipeAdv = (PipeAdvertisement) AdvertisementFactory.newAdvertisement(MimeMediaType.XMLUTF8, is);
            is.close();
          
            System.out.println("ok here");
             //discoSvc.publish( pipeAdv, DiscoveryService.ADV);
              
          
             System.out.println("ok here too");
            // we want to block until a connection is established
          
        } catch (Exception e) {
             pipeAdv = (PipeAdvertisement)AdvertisementFactory. newAdvertisement(

                    PipeAdvertisement.getAdvertisementType());

               PipeID pid = IDFactory.newPipeID(group.getPeerGroupID());
               pipeAdv.setName("serve");
               pipeAdv.setPipeID(pid);

               //save pipeAd in file

               Document pipeAdDoc = pipeAdv.getDocument(new MimeMediaType ("text/xml"));

               try {

                     FileOutputStream os = new FileOutputStream(PIPE_ADV_FILE);

                     pipeAdDoc.sendToStream(os);

                     os.flush();

                     os.close();

                     System.out.println("Wrote pipe advertisement to disk.");

               } catch (IOException ex) {

                     System.out.println("Can't save pipe advertisement to file " +

                            PIPE_ADV_FILE);

            System.exit(-1);
            System.out.println("failed to read/parse pipe advertisement");
            e.printStackTrace();
            System.exit(-1);
               }

        }
           try {

             
               discoSvc.remotePublish(pipeAdv, DiscoveryService.ADV);

               System.out.println("Published module spec adv");

        } catch (Exception e) {

               System.out.println("Trouble publishing module spec adv: " +

                       e.getMessage());

}


//等待连接

while(true){
                                     System.out.println("starting ServerPipe");
                          try {                         
                               serverPipe = new JxtaServerPipe(group, pipeAdv);
                                serverPipe.setPipeTimeout(0);
                                System.out.println("starting");
                                bipipe = serverPipe.accept();
                                  System.out.println("starting1 ");
                                if (bipipe != null ) {
                                  System.out.println("BiDi Pipe created");
                                
                                  receiveAndSendTestMessage(bipipe);

                                }
                              } catch (Exception e) {
                                e.printStackTrace();
                                System.out.println("not created");
                                return;
                              }
          
          }

        }

//发消息       
      private void receiveAndSendTestMessage (JxtaBiDiPipe pipe) {
        try {
         
          Message  msg = new Message();          
          StringMessageElement sme = new StringMessageElement(SenderMessage, ReturnCred, null);
          msg.addMessageElement(null, sme);
          StringMessageElement sme1 = new StringMessageElement(peerGroupID, group.getPeerGroupID().toString(), null);
          msg.addMessageElement(null, sme1);
          StringMessageElement sme2 = new StringMessageElement(peerID, group.getPeerID().toString(), null);
          msg.addMessageElement(null, sme2);
            System.out.println("Sending back 'Hello World'");
            pipe.sendMessage(msg);
          }
          catch (Exception ie) {
            ie.printStackTrace();
          }
      }
 
//接收消息     
public void pipeMsgEvent(PipeMsgEvent ev) {
           Message msg = ev.getMessage();
           MessageElement msgElement = msg.getMessageElement(null, SenderMessage);
           xiaoxi=msgElement.toString();
            System.out.println(xiaoxi);
          // Get message
          if (msgElement.toString() == null) {
            System.out.println("null msg received");
          }
       
}
     
}
  
客户端代码：

package primecruncher;

import net.jxta.peergroup.PeerGroup;
import net.jxta.peergroup.PeerGroupFactory;
import net.jxta.endpoint.StringMessageElement;
import net.jxta.util.JxtaBiDiPipe;
import net.jxta.discovery.DiscoveryService;
import net.jxta.discovery.DiscoveryListener;
import net.jxta.discovery.DiscoveryEvent;
import net.jxta.pipe.PipeService;
import net.jxta.pipe.PipeMsgListener;
import net.jxta.exception.PeerGroupException;
import net.jxta.protocol.DiscoveryResponseMsg;
import net.jxta.protocol.PipeAdvertisement;
import net.jxta.pipe.PipeMsgEvent;
import net.jxta.rendezvous.RendezVousService;
import net.jxta.endpoint.Message;
import java.util.*;
import net.jxta.endpoint.MessageElement;
public class PrimeClient implements DiscoveryListener,PipeMsgListener{
    private static PeerGroup group;
private Message msg,msg1;
    private static DiscoveryService discoSvc;
    private static PipeService pipeSvc;
    String b;
    String xiaoxi; 
    PipeAdvertisement pipeAdvert;
    private RendezVousService rdv;
  
   
    public PrimeClient(){}
         public static void main(String[] args)
         {
               PrimeClient cl = new   PrimeClient();
try{
               cl.startJxta();
               cl.doDiscovery();                            
               System.out.println("wuyichang");
        }catch(NullPointerException ee)
        { System.out.println("yichang");}

   }
//初始化
private void startJxta() {

               try {
                       group = PeerGroupFactory.newNetPeerGroup();                    
                       discoSvc = group.getDiscoveryService();
              System.out.println("startJxta");
                       pipeSvc = group.getPipeService();                      
               } catch (PeerGroupException e) {
                       System.out.println("Can't create net peer group: " +
                               e.getMessage());
                       System.exit(-1);
               }
        }
//远程搜索
private void doDiscovery()
         { discoSvc.addDiscoveryListener(this);
           
            int peerQueryID = discoSvc.getRemoteAdvertisements(null, DiscoveryService.ADV,
                    null, null, 5);
             System.out.println("sousuo");
         }
//监听搜索结果并作出处理
public void discoveryEvent(DiscoveryEvent ev) 
{    DiscoveryResponseMsg res = ev.getResponse();
      Enumeration er = res.getAdvertisements();
   if (er != null ) {
            while (er.hasMoreElements())
            {
                pipeAdvert = (PipeAdvertisement)er.nextElement();
                 System.out.println("faxianguanggao");
            }
                    }

//建立连接发送消息
     try{
      JxtaBiDiPipe   bidipipe =  new  JxtaBiDiPipe(group,pipeAdvert,20000,this ,true );
      msg = new Message();           
      StringMessageElement sme = new StringMessageElement("SenderMessage", "ReturnCred", null);
      msg.addMessageElement(null, sme);
      StringMessageElement sme1 = new StringMessageElement("a", group.getPeerGroupID().toString(), null);
      msg.addMessageElement(null, sme1);
      StringMessageElement sme2 = new StringMessageElement("b", group.getPeerID().toString(), null);
      msg.addMessageElement(null, sme2);
      bidipipe.sendMessage(msg);
       System.out.println("fasong");
       }catch(Exception e)
        {
            e.printStackTrace();
            System.out.println("not created");
        }
}
//接收消息
public void pipeMsgEvent(PipeMsgEvent ev) {
            msg1 = ev.getMessage();
           MessageElement msgElement = msg1.getMessageElement(null, "SenderMessage");
           xiaoxi=msgElement.toString();
           System.out.println(xiaoxi);
          if (msgElement.toString() == null) {
            System.out.println("null msg received");
          }
}

}