java - 多线程服务器客户端地址已被使用

Question

我想做的是在服务器中创建接收者类，该服务器接收从客户端发送的消息，并在客户端中创建发送者类。我试图首先在服务器中制作接收器，因为在学习之后我可能会弄清楚如何在客户端中做到这一点。但这样做会给我 java.net.BindException:地址已在使用中:JVM_Bind 。我认为这是因为我在接收器中有另一个 Server server = new Server(); 。我该如何解决这个问题？

服务器.java

package MultithreadingServerClient;

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

public class Server {
    ServerSocket serverSocket = new ServerSocket(3000);
    Socket socket = serverSocket.accept();
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    PrintWriter printWriter = new PrintWriter(socket.getOutputStream(), true);

    public Server() throws IOException {
    }

    public static void main(String[] args) {
        Thread serverSender = new Thread(new ServerSender());
        Thread serverReceiver = new Thread(new ServerReceiver());
        serverSender.start();
        serverReceiver.start();
    }
}

// Sender class
class ServerSender implements Runnable {

    @Override
    public void run() {
        try {
            Server serve = new Server();
            Scanner scanner = new Scanner(System.in);

            String msg = "";
            while (!msg.equalsIgnoreCase("exit")) {
                System.out.print("Server: ");
                msg = scanner.nextLine();

                serve.printWriter.println(msg);
            }

        } catch (IOException e) {
            System.err.println("Sender Error " + e);
        }
    }
}

class ServerReceiver implements Runnable {
    @Override
    public void run() {
        try {
            Server server = new Server();

            System.out.println(server.bufferedReader.readLine());
        } catch (IOException e) {
            System.err.println("Receiver Error " + e);
        }
    }
}

Client.java

package MultithreadingServerClient;

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

public class Client {
    Socket socket = new Socket("localhost", 3000);
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    PrintWriter printWriter = new PrintWriter(socket.getOutputStream());

    public Client() throws IOException {
    }

    // Receive messages
    public static void main(String[] args) {
        try {
            Client client = new Client();

            while (true) {
                System.out.println("Server: " + client.bufferedReader.readLine());
            }
        } catch (IOException e) {
            System.out.println("Server Closed!");
        }
    }
}

class ClientSender implements Runnable {
    @Override
    public void run() {
        try {
            Client client = new Client();

            client.printWriter.println("Test message: send to Server");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Answer 1

不要创建 Server 的多个实例，您可以在 main 中创建实例，然后将 bufferedReader 传递给接收器类，以及发送者类的 printWriter。

发件人类别:

class ServerSender implements Runnable {


    private PrintWriter writer;

    public ServerSender(PrintWriter printWriter){

        writer = printWriter;
    }

    @Override
    public void run() {
        try {

            Scanner scanner = new Scanner(System.in);

            String msg = "";
            while (!msg.equalsIgnoreCase("exit")) {
                System.out.print("Server: ");
                msg = scanner.nextLine();

                writer.println(msg);
            }

        } catch (IOException e) {
            System.err.println("Sender Error " + e);
        }
    }
}

接收器类:

class ServerReceiver implements Runnable {

    private BufferedReader reader;

    public ServerReceiver(BufferedReader bufferedReader){

       reader = bufferedReader;

    }

    @Override
    public void run() {
        try {

            System.out.println(reader.readLine());
        } catch (IOException e) {
            System.err.println("Receiver Error " + e);
        }
    }
}

服务器中的方法main:

public static void main(String[] args) {

    Server serve = new Server();
    Thread serverSender = new Thread(new ServerSender(serve.printWriter));
    Thread serverReceiver = new Thread(new ServerReceiver(serve.bufferedReader));
    serverSender.start();
    serverReceiver.start();
}