Question

我有一个客户端 - 服务器应用程序。现在，我正在尝试测试从客户端向服务器发送消息，然后从服务器读取它们。我正在使用ObjectInputStream和ObjectOutputStream在客户端和服务器之间传输邮件对象。

但是，当我尝试从客户端编写对象时，会产生SocketException。

服务器代码：

while (true) {
        try {

            log.trace("Waiting for connection.");
            Socket clientSocket = socket.accept();
            log.trace("Socket connected");
            /* create thread */
            new Thread(new RequestRunner(clientSocket, serverID)).start();


        } catch (SocketTimeoutException e) {
            log.trace("Socket timed out.");
            socket.close();
            break;
        } catch (IOException e) {
            log.error("Cannot accept connection...");
            break;
        }
    }

服务器线程：

public class RequestRunner implements Runnable {

....

public RequestRunner(Socket socket, UUID serverID) {
    client = socket;
    this.serverID = serverID;
}

/**
 * Start the thread for the request
 */
public void run() {


    log.trace("Thread started for socket");

    try {
        out = new ObjectOutputStream(client.getOutputStream());
        in = new ObjectInputStream(client.getInputStream());
    } catch (IOException e) {
        log.error("Cannot intialize streams...");
        return;
    }

    while(client.isConnected()) {
    /* initialize streams */
        try {


        /* read message */

            Object obj = in.readObject(); // does not block
            MessageFrame msg = (MessageFrame) obj;
            processRequest(msg);

        } catch (IOException e) {

            ; // triggers everytime
            //log.error("IO error occured while trying to get input/output stream from socket");


        } catch (ClassNotFoundException e) {
            log.error("Cannot read MessageFrame");
        }
    }
}

}

客户代码：

  public void init(int port) throws IOException {

    log.trace("intializing to port " + port);
    clientID = UUID.randomUUID();
    socket = new Socket("0.0.0.0",port);
    out = new ObjectOutputStream(socket.getOutputStream());
    in = new ObjectInputStream(socket.getInputStream());

}

public void sendEcho() throws Exception {

    while(socket.isConnected()) {

        try {
            log.trace("Sending echo..");
            msg = new EchoMessage(clientID);
            curMsgID = msg.getMsgID();
            out.writeObject(msg);   // throws SocketException, socket closed
            out.flush();
            break;
        } catch (SocketException e) {
            log.error ("Cannot send echo.. socket closed.");
            break;
        } catch (IOException e) {
            continue;
        }
    }
}

语句out.writeObject(msg)导致ServerSocket例外Socket closed作为原因。并且服务器不注册从in.readObject()接收对象。

netstat显示已建立的连接，当我尝试编写对象时发生错误。

我做错了什么？

Answer 1

您应该只有一个InputStream和一个OutputStream。

out = new ObjectOutputStream(client.getOutputStream());
in = new ObjectInputStream(client.getInputStream());

应该是：

out = client.getOutputStream(); 
in = client.getInputStream()

在从套接字获取流时，您应该在客户端代码中更改它。

客户端中的ObjectOutputStream导致ServerException

1 个答案: