当我将多个客户端同时连接到 Java 服务器时，套接字写入错误

Posted 2023-02-16

【中文标题】当我将多个客户端同时连接到 Java 服务器时，套接字写入错误

【英文标题】：Socket write error when i connect multiple client to java server simultaneously

【发布时间】：2012-09-11 07:00:39

【问题描述】：

我正在创建一个桌面应用程序，其中多个客户端必须使用它们之间的套接字连接来连接到服务器。我成功连接了它们，但是当我将多个客户端同时连接到服务器时出现问题，服务器出现错误“socket write error” 我的代码在下面请给我一个答案..

public class SocketConnection implements Runnable 
    // password of oracle database

    ServerSocket serverSocket = null;
    Socket socket = null;
    DataInputStream dataInputStream = null;
    DataOutputStream dataOutputStream = null;
    Socket clientSocket = null;
    DBConnection dbConnection;


    public SocketConnection() 
        // TODO Auto-generated constructor stub

        dbConnection = new DBConnection();

        if (con != null) 

            serverSocket = dbConnection.createSocket();

            if (serverSocket != null) 

                System.out.println("Server Started. Looking for the connections.");
                System.out.println("Listening Port:8888.......");
            



            Thread t = new Thread(this);
            t.start();
        

    


    @Override
    public void run() 
        // TODO Auto-generated method stub
        while (true) 
            try 
                clientSocket = serverSocket.accept();
                System.out.println("Connection Accepted");
                Connect m_connect = new Connect(clientSocket);

             catch (IOException e) 
                // TODO Auto-generated catch block
                e.printStackTrace();
            

        

    

    public class Connect implements Runnable 
        Socket clientSocket = null;
        Thread t = null;
        private ResultSet res1;
        private ResultSet res2;
        Statement stmt;
        private File mkFolder;

        public Connect(Socket clientSocke) 
            // TODO Auto-generated constructor stub
            this.clientSocket = clientSocke;

            try 

                stmt = con.createStatement();
             catch (SQLException e) 
                // TODO Auto-generated catch block
                e.printStackTrace();
            
            try 

             catch (Exception e) 
                // TODO: handle exception
                e.printStackTrace();
            
            t = new Thread(this);
            t.start();
        

        @Override
        public void run() 

            try 
                dataInputStream = new DataInputStream(
                        clientSocket.getInputStream());
                dataOutputStream = new DataOutputStream(
                        clientSocket.getOutputStream());
                System.out.println("Connection established::"
                        + clientSocket.getInetAddress());
                String pass = dataInputStream.readUTF();
                System.out.println(pass);
                if (pass.equals("1")) 
                    //here is read n write operation

                 else if (pass.equals("3")) 

                    //here is read n write operation

                 else if (pass.equals("2")) 

                    //here is read n write operation

                 else if (pass.equals("4")) 
                    //here is read n write operation

                 else if (pass.equals("5")) 
                    //here is read n write operation

                
             catch (IOException e) 
                // TODO Auto-generated catch block
                e.printStackTrace();
             finally 
                if (socket != null) 
                    try 
                        socket.close();
                     catch (IOException e) 
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    
                

                if (dataOutputStream != null) 
                    try 
                        dataOutputStream.close();
                     catch (IOException e) 
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    
                

                if (dataInputStream != null) 
                    try 
                        dataInputStream.close();
                     catch (IOException e) 
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    
                
                if (stmt != null) 
                    try 
                        stmt.close();
                     catch (SQLException e) 
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    
                




    

【问题讨论】：

你知道是哪一行报错了吗？

读写操作出错..

哪个读/写操作，在代码中抛出了那个错误？很明显这是一个读/写操作，因为它在错误消息的标题中。

这是我的堆栈跟踪... Unknown Source) at java.net.SocketOutputStream.write(Unknown Source) at java.io.DataOutputStream.write(Unknown Source) at java.io.DataOutputStream.writeUTF(Unknown Source) at java.io.DataOutputStream.writeUTF(Unknown Source) ) 在 ConnectOracle$SocketConnection$Connect.run(ConnectOracle.java:529) n 第 529 行是.. dataOutputStream.writeUTF(res2 .getString(t));通过=1;

【参考方案1】：

您为什么要以这种低级方式执行此操作？选择一个有据可查的 API 并通过它进行通信！

您是否已经阅读过这样的文章：Multithread client server chat on sockets. Load test. recv failed

【讨论】：

我不知道..如何实现这个

很抱歉，我不能教你开发协议。为什么你不使用 RMI 或其他？然后你可以发送愚蠢的简单 pojos 来代表你的命令并返回一些数据。但我永远不会自己实现这个，你尝试什么

感谢您的考虑。！！但是我的问题现在已经解决了。。我也会尝试学习这个。。