回调客户端的远程对象

回调客户端的远程对象有问题

要求客户端也在公网开放端口才行 

StockQuote.java 

package stock;

import java.rmi.*;

/** 客户端的远程对象接口 */

public interface StockQuote extends Remote{

    public void quote(String stockSymbol, double price)throws RemoteException;

}

 

//StockQuoteImpl.java 

package stock;

import java.rmi.*;

import java.rmi.server.*;

public class StockQuoteImpl extends UnicastRemoteObject

                                      implements StockQuote{

  public StockQuoteImpl()throws RemoteException{}

  public void quote(String symbol, double value)throws RemoteException{

    System.out.println(symbol+": "+value);

  }

}

 

//StockQuoteRegistry.java 

package stock;

import java.rmi.*;

public interface StockQuoteRegistry extends Remote{

  public void registerClient(StockQuote client)throws RemoteException;

  public void unregisterClient(StockQuote client)throws RemoteException;

}

 

//StockQuoteRegistryImpl.java

 

package stock;

import java.rmi.*;

import java.rmi.server.*;

import java.util.*;

public class StockQuoteRegistryImpl extends UnicastRemoteObject

           implements StockQuoteRegistry, Runnable{

  protected HashSet<StockQuote> clients;

  public StockQuoteRegistryImpl()throws RemoteException{

        clients = new HashSet<StockQuote>();

  }

  public void run(){

    //创建一些股票代号

    String[] symbols = new String[] {"SUNW", "MSFT", "DAL", "WUTK", "SAMY", "KATY"};

    Random rand = new Random();

    double values[] = new double[symbols.length];

    //为每个股票分配任意价格

    for(int i=0; i < values.length; i++){

      values[i] = 25.0 + rand.nextInt(100);

    }

    for (;;){

      //随机取出一个股票

      int sym = rand.nextInt(symbols.length);

 

      // 修改股票的价格

      int change = 100 - rand.nextInt(201);

      values[sym] = values[sym] + ((double) change) / 100.0;

      if (values[sym] < 0) values[sym] = 0.01;

      Iterator<StockQuote> iter = clients.iterator();

      while (iter.hasNext()){

        StockQuote client =  iter.next();

        try{

          client.quote(symbols[sym], values[sym]);

        }catch (Exception exc){

           System.out.println("删除一个无效的客户");

           iter.remove();

        }

      }

      try { Thread.sleep(1000); } catch (Exception ignore) {}

    }

  }

  public void registerClient(StockQuote client)throws RemoteException{

    System.out.println("加入一个客户");

    clients.add(client);

  }

  public void unregisterClient(StockQuote client)throws RemoteException{

    System.out.println("删除一个客户");

    clients.remove(client);

  }

}

//SimpleClient.java 

 

 

package stock;

 

import java.rmi.*;

import javax.naming.*;

public class SimpleClient{

  public static void main( String args[] ){

    String url="rmi://localhost/";

    try{

      Context namingContext=new InitialContext();

      StockQuoteRegistry registry=

          (StockQuoteRegistry           )namingContext.lookup(url+"StockQuoteRegistry");

      

      StockQuote client=new StockQuoteImpl();

      registry.registerClient(client);    

  

    }catch( Exception e){

       e.printStackTrace();

    }

  }

}

 

// SimpleServer.java

package stock;

import java.rmi.*;

import javax.naming.*;

public class SimpleServer{

  public static void main( String args[] ){

    try{

       StockQuoteRegistryImpl registry=new StockQuoteRegistryImpl();

 

       Context namingContext=new InitialContext();

       namingContext.rebind( "rmi:StockQuoteRegistry", registry);

       System.out.println( "服务器注册了一个StockQuoteRegistry对象" );

       new Thread(registry).start();

    }catch(Exception e){

       e.printStackTrace();

    } 

  }

}