Java 中的 Rmi - 需要修改的聊天应用程序,但是如何修改?

Rmi in Java - Chat Application with need of modification, but How?

我已经制作了 java RMI 应用程序 - 聊天。

聊天Class:

public class Chat extends UnicastRemoteObject implements ChatInterface  {

    public String name;
    public ChatInterface client=null;

    public Chat(String n)  throws RemoteException { 
        this.name=n;   
    }
    public String getName() throws RemoteException {
        return this.name;
    }

    public void setClient(ChatInterface c){
        client=c;
    }

    public ChatInterface getClient(){
        return client;
    }

    public void send(String s) throws RemoteException{
        System.out.println(s);
    }   
}

聊天客户端class:

    import java.rmi.*;
    import java.rmi.server.*;
    import java.util.*;

    public class ChatClient {
        public static void main (String[] argv) {
            try {
                System.setProperty("java.rmi.server.hostname","127.0.0.1");
                System.setSecurityManager(new RMISecurityManager());
                Scanner s=new Scanner(System.in);
                System.out.println("Enter Your name and press Enter:");
                String name=s.nextLine().trim();
                ChatInterface client = new Chat(name);
                ChatInterface server = (ChatInterface)Naming.lookup("rmi://localhost/ABC");
                String msg="["+client.getName()+"] got connected";
                server.send(msg);
                System.out.println("[System] Chat Remote Object is ready:");
                server.setClient(client);

                while(true){
                    msg=s.nextLine().trim();
                    msg="["+client.getName()+"] "+msg;                  
                    server.send(msg);
                }

            }catch (Exception e) {
                System.out.println("[System] Server failed: " + e);
            }
        }
    }

ChatInterface 界面:

public interface ChatInterface extends Remote{
    public String getName() throws RemoteException;
    public void send(String msg) throws RemoteException;
    public void setClient(ChatInterface c)throws RemoteException;
    public ChatInterface getClient() throws RemoteException;
}

聊天服务器class:

public class ChatServer {
    public static void main (String[] argv) {
        try {
            System.setProperty("java.rmi.server.hostname","127.0.0.1");
            System.setSecurityManager(new RMISecurityManager());
            Scanner s=new Scanner(System.in);
            System.out.println("Enter Your name and press Enter:");
            String name=s.nextLine().trim();

            Chat server = new Chat(name);   

            Naming.rebind("rmi://localhost/ABC", server);

            System.out.println("[System] Chat Remote Object is ready:");

            while(true){
                String msg=s.nextLine().trim();
                if (server.getClient()!=null){
                    ChatInterface client=server.getClient();
                    msg="["+server.getName()+"] "+msg;
                    client.send(msg);
                }   
            }
        }catch (Exception e) {
            System.out.println("[System] Server failed: " + e);
        }
    }
}

Chat - 两个项目中的相同代码

ChatInterface - 两个项目中的代码也相同

ChatClient - ChatServer - 它们具有不同的代码


看起来像这样:How it looks inside Eclipse (hierarchy)

问题是,这个聊天功能类似于... 我们收到了所有消息(比如整个历史记录)但是当用户发送新消息时。 比如我们有user1,user2,user3.

而 User3 什么也看不到,因为没有发送任何消息,所以什么也没有。

这很糟糕:/。这就像用户必须发送一些东西才能收到消息。即使只有"space",但还是有的。否则他不会收到任何消息。

我需要让它在一个用户发送新消息时自动向所有用户发送新消息。喜欢"update".'

需要像

public interface ChatInterface extends Remote{
    public String getName() throws RemoteException;
    public void send(String msg) throws RemoteException;
    public void setClient(ChatInterface c)throws RemoteException;
    public ChatInterface getClient() throws RemoteException;
}

问题从这里开始。 setClient() 的本质是服务器一次只知道一个客户端。服务器当然应该有一个 list 客户端,方法应该是 addClient(ChatInterface c).

getClient() 作为远程方法的目的让我难以理解。