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Java无法同时读写套接字

[英]Java cannot read and write to socket at the same time

我正在尝试使用Java套接字构建一个简单的多客户端聊天应用程序。 我这样做的方法是让客户端类连接到服务器类,该服务器类等待客户端连接并创建一个新线程来处理该客户端(在其中读取和写入套接字连接)。 客户端还读取和写入与此线程的套接字连接。 但是,当客户端写入套接字的输出流时,服务器将不会响应。 这里发布了一个类似的问题:

您可以同时写入套接字的输入和输出流吗?

这里的答案之一是,您可以同时读取和写入套接字,只要在单独的线程中完成对套接字的读取即可。

这是我的客户应用程序:

    public class Client {

    Socket socket;

    public static void main(String[] args) {
        new Client();
    }

    public Client() {
        try {
            socket = new Socket("localhost", 4444);

            new Thread() {

                @Override
                public void run() { //read from the input stream

                    try(
                        BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                    ) {
                        String line;
                        while( (line = in.readLine()) != null ) {
                            System.out.println("Server said: " + line);
                        }
                    } catch(IOException e) {

                    }

                }

            }.start();

            //write to output stream
            try(
                PrintWriter out = new PrintWriter(new OutputStreamWriter(socket.getOutputStream()));
                Scanner userInput = new Scanner(System.in);
            ){
                System.out.println("Enter Something: ");
                if(userInput.hasNextLine()) {
                    out.println(userInput.nextLine());
                }
            } catch (IOException e) {

            }

        } catch(IOException e) {

        }


    }
}

而我的服务器应用程序:

public class Server {
    ServerSocket ss;


    public static void main(String[] args) {
        new Server();
    }

    public Server() {
        System.out.println("Server Running...");
        try {
            ss = new ServerSocket(4444);

            while(true) {


                Socket socket = ss.accept();
                new Thread() { //create new thread connection to client
                    @Override
                    public void run() {

                        new Thread() { //thread that reads inputstream
                            @Override
                            public void run() {

                                try(
                                    BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                                ) {
                                    String line;
                                    while( (line = in.readLine()) != null ) {
                                        System.out.println("Client said: " + line);
                                        //The problem seems to lie here.
                                    }
                                } catch(IOException e) {

                                }

                            }
                        }.start();

                        //write to outputstream
                        try (
                            PrintWriter out = new PrintWriter(new OutputStreamWriter(socket.getOutputStream()));
                        ) {
                            String sendToClient = "Hey, my name is Server007 B)";

                            out.println(sendToClient);

                        } catch(IOException e) {

                        }
                    }
                }.start();

            }


        } catch (IOException e) {}
    }
}

我将运行服务器,然后运行客户端,在客户端输出

Server said: Hey, my name is Server007
Enter something: 
Hello! <- enter anything

但服务器不打印“客户说:您好!” 就像我期望的那样。 我希望我的问题已经足够清楚了,谢谢。

好的,所以我弄清楚了,如果有人犯同样的错误,我将回答我自己的问题。 PrintWriter构造函数应为:

PrintWriter out = new PrintWriter(socket.getOutputStream(), true);

不是这个:

PrintWriter out = new PrintWriter(new OutputStreamWriter(socket.getOutputStream()));

或者,我可以这样做:

BufferedWriter out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));

我一定对BufferedWriter和PrintWriter:P感到困惑

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