我尝试将多行代码从客户端发送到服务器。

以下是服务器端的代码

            in = new BufferedReader(new InputStreamReader(client.getInputStream()));
            out = new PrintWriter(client.getOutputStream(), true);
            //read client input
            //multi line 
            //https://stackoverflow.com/questions/43416889/java-filereader-only-seems-to-be-reading-the-first-line-of-text-document?newreg=2f77b35c458846dbb1290afce8853930
            String line = "";
            while((line =in.readLine()) != null) {
                System.out.println(line);
            System.out.println("is it here?");

下面是客户端的代码：

    BufferedReader input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    BufferedReader keyboard = new BufferedReader(new InputStreamReader(System.in));
    PrintWriter out = new PrintWriter(socket.getOutputStream(),true);
    while (true) {
        System.out.print("> ");
        //content server input command (put, lamport clock, message)
        String command = keyboard.readLine();
        if (command.equals("quit")){
            break;
        //read from CSDB/txt1.txt
        String message = readFileReturnString("CSDB/txt1.txt", StandardCharsets.UTF_8);
        System.out.println(message);
        //send to clientHandler through PrintWriter
        out.println(command + " 3 \n" + message);
        //receive response from ClientHandler (lamport clock)
        String serverResponse = input.readLine();
        System.out.println(serverResponse + socket);
    }

服务器端可以打印出从客户端发送的所有文本。但是，while循环没有中断，System.out.println(“它在这里吗？”)；从未执行过。

我可以知道为什么和如何解决这个问题吗？