Java Socket 为什么服务器无法回复客户端

Question

我想编写代码让客户端发送一个字符串到服务器，服务器打印该字符串并回复一个字符串，然后客户端打印服务器回复的字符串。
我的服务器

public class Server {

public static void main(String[] args) throws IOException {
    ServerSocket ss = null;
    Socket s = null;
    try {
        ss = new ServerSocket(34000);
        s = ss.accept();
        BufferedReader in = new BufferedReader(new InputStreamReader(
                s.getInputStream()));
        OutputStreamWriter out = new OutputStreamWriter(s.getOutputStream());

        while (true) {
            String string = in.readLine();
            if (string != null) {
                System.out.println("br: " + string);

                if (string.equals("end")) {
                    out.write("to end");
                    out.flush();
                    out.close();
                    System.out.println("end");
                    // break;
                }
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        s.close();
        ss.close();
    }
}
}

我的客户:

public class Client {
public static void main(String[] args) {
    Socket socket =null;


    try {
        socket = new Socket("localhost", 34000);
        BufferedReader in =new BufferedReader(new InputStreamReader(socket.getInputStream()));
        OutputStreamWriter out = new OutputStreamWriter(socket.getOutputStream());

        String string = "";
        string = "end";
        out.write(string);
        out.flush();
        while(true){
            String string2 = in.readLine();
            if(string2.equals("to end")){
                System.out.println("yes sir");
                break;
            }
        }


    }  catch (Exception e) {
        e.printStackTrace();
    }finally{
        try {
            System.out.println("closed client");
            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}
}

有什么问题吗？如果我删除客户端类中的代码“while(true) ...”，就可以了。

Answer 1

您应该在写入流的字符串末尾添加“\r\n”。

示例:

客户端:

    string = "end";
    out.write(string + "\r\n");
    out.flush();

服务器:

    out.write("to end" + "\r\n");
    out.flush();
    out.close();
    System.out.println("end");
                // break;