在后台接收消息

Question

Java Client-Server。 有必要在后台接收来自客户端的消息。 我正在尝试在后台接收消息：

.BAT

Bacground部分：

public Server() throws IOException {
           try {
        serverSocket=new ServerSocket(1234);
        fromclient= serverSocket.accept();
        System.out.println("Socket created");
    } catch (IOException e) {
        e.printStackTrace();
        System.out.println("Socket not created");
    }
    try {
        in  = new BufferedReader(new
                InputStreamReader(fromclient.getInputStream()));
    } catch (IOException e) {
        e.printStackTrace();
    }
    out = new PrintWriter(fromclient.getOutputStream(),true);
    String         input,output;
}

并在客户端部分发送消息：

 public void run(ServerSocket welcomeSocket) throws IOException {
        Socket connectionSocket = welcomeSocket.
                accept();
        BufferedReader inFromClient =
                new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
        DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
        clientSentence = inFromClient.readLine();
        System.out.println(clientSentence);
        capitalizedSentence =
                clientSentence.toUpperCase() + '\n';
        outToClient.writeBytes(capitalizedSentence);
    }

但没有任何反应。

Answer 1

您在端口1234上打开了一个ServerSocket，然后在Socket上打开了6789.尝试使用相同的端口：）