Java ServerSocket 不会发送或接收来自客户端的消息

Question

我有这两个类Client.java和Server.java，每个都包含一个main方法。思路很简单，里面的代码也很相似。 objective 我试图实现的是打开一个 服务器 ，它使用 ServerSocket 侦听特定端口，然后打开一个 客户端 并使用 Socket 连接到服务器，以便我最终可以将消息从 client 发送到 server 并反向发送直到我关闭连接。

到目前为止，我尝试了最简单的示例，在端口 4444 上打开了 server，然后在 same PC 我打开了一个客户端连接到地址 127.0.0.1（本地主机），在端口 4444 上。一切运行顺利, 每次都成功建立连接，除了它不会发送任何消息，无论是从服务器到客户端还是客户端到服务器。

最后一个问题是，我应该怎么做才能在服务器和客户端之间交换消息？我应该修改什么？

Client.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class Client {

    private static Socket client;
    private static BufferedReader in, console;
    private static PrintWriter out;

    private static String serverAddress;
    private static int port;

    public static void main(String[] args) {

        try {
            console = new BufferedReader(new InputStreamReader(System.in));

            System.out.print("Connect to server address (example 192.168.10.11): ");
            serverAddress = console.readLine();

            System.out.print("Port: ");
            port = Integer.parseInt(console.readLine());

            System.out.println("\nTrying to connect...");
            client = new Socket(serverAddress, port);

            System.out.println("Connected to " + client.getRemoteSocketAddress());
            in = new BufferedReader(new InputStreamReader(client.getInputStream()));
            out = new PrintWriter(client.getOutputStream());

            out.write("Connected!!!!!!");

            Thread input = new Thread() {

                public void run() {
                    String tmp;

                    try {
                        while((tmp = in.readLine()) != null) {
                            System.out.println("Server: " + tmp);
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            };

            Thread output = new Thread() {

                public void run() {
                    String tmp;

                    try {
                        while((tmp = console.readLine()) != null) {
                            out.print(tmp);
                        }
                    } catch(IOException e) {
                        e.printStackTrace();
                    }
                }
            };


            input.start();
            output.start();

            while(true) {
                if(!input.isAlive() && !output.isAlive()) {
                    client.close();

                    in.close();
                    console.close();
                    out.close();

                    break;
                }
            }

        } catch (IOException e) {   
            e.printStackTrace();
        }

    }

}

Server.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {

    private static ServerSocket serverSocket;
    private static Socket server;
    private static BufferedReader in, console;
    private static PrintWriter out;

    private static int port;

    public static void main(String[] args) {


        try {
            console = new BufferedReader(new InputStreamReader(System.in));

            System.out.print("Open server on port (example 1234): ");
            port = Integer.parseInt(console.readLine());

            System.out.println("Server open");
            serverSocket = new ServerSocket(port);

            System.out.println("Waiting for a client to connect...\n");
            server = serverSocket.accept();

            System.out.println("Client " + server.getRemoteSocketAddress() + " connected!");
            in = new BufferedReader(new InputStreamReader(server.getInputStream()));
            out = new PrintWriter(server.getOutputStream(), true);

            Thread input = new Thread() {

                public void run() {
                    String tmp;

                    try {
                        while((tmp = in.readLine()) != null) {
                            System.out.println("Client: " + tmp);
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            };

            Thread output = new Thread() {

                public void run() {
                    String tmp;

                    try {
                        while((tmp = console.readLine()) != null) {
                            out.print(tmp);
                        }
                    } catch(IOException e) {
                        e.printStackTrace();
                    }
                }
            };

            input.start();
            output.start();

            while(true) {
                if(!input.isAlive() && !output.isAlive()) {
                    serverSocket.close();
                    server.close();

                    in.close();
                    console.close();
                    out.close();

                    break;
                }
            }

        } catch (IOException e1) {
            e1.printStackTrace();
        }

    }

}

Answer 1

你是在读台词，但不是在拧台词。而不是 out.write() 和 out.print() 你应该使用 out.println().

Java ServerSocket 不会发送或接收来自客户端的消息

Java ServerSocket won't send or receive messages from client

java

sockets

client-server

serversocket

server

Client.java

Server.java