server.java

适于初学者学习的基于rmi的java聊天器

package server;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import java.rmi.server.UnicastRemoteObject;
import java.util.Enumeration;
import java.util.Hashtable;

import message.MessageReceiver;
import message.MessageServer;
/**
 * coder: taie
 */
public class Server extends UnicastRemoteObject implements MessageServer{
    // a hashtable    存储用户
    static Hashtable receivers=new Hashtable(5);
    public Server()throws RemoteException{
        super();
    }
    public void send(String name,String message)throws RemoteException{
        for(Enumeration e=receivers.elements();e.hasMoreElements();)
        {MessageReceiver m=(MessageReceiver)e.nextElement();
            m.print(name+":"+message);
        }
    }
    
    public int register(String name,MessageReceiver m){
        int retval=MessageServer.FAILURE;
        // 空注册检测
        if((name!=null)&&(m!=null)){
           //唯一用户名 
            if(receivers.get(name)==null)
            {
                receivers.put(name,m);
                System.out.println("added "+name);
                retval=MessageServer.success;
            }else{
                System.out.println("Could not add client because"+name
                        +"already exists on server.");
            }
        }
        return retval;
    }
    public static void main(String[] args){
       // System.setSecurityManager(new RMISecurityManager());
        try{
            //create an instance 
            MessageServer srv=new Server();
            
            //server类创建注册表
              Registry reg=LocateRegistry.createRegistry(
              Registry.REGISTRY_PORT);
             reg.rebind(MessageServer.SERVER_NAME,srv);
              System.out.println("Server bound and Started!");
        }catch(Exception e){
            System.err.println("Server exception:"+e.getMessage());
            e.printStackTrace();
            }
    }
}