无法在java中的2台PC套接字之间将客户端连接到服务器答案

【问题标题】：Can't connect client to server between 2 PCs socket in java无法在java中的2台PC套接字之间将客户端连接到服务器
【发布时间】：2022-01-14 12:08:45
【问题描述】：

我有一个问题，当我在同一台 PC 上创建 2 个文件（Client.java 和 Server.java）时，它可以工作。但是当我将 Client.java 文件发送到另一台 PC 时，它不起作用。我也关闭了防火墙，但它仍然不起作用。

类 Sever.java：

import java.io.*;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {

    public static void main(String[] args) throws IOException {
        try {
            System.out.println("loading..");
            ServerSocket serverSocket = new ServerSocket(6667);
            Socket socket = serverSocket.accept();
            DataInputStream dataInputStream = new DataInputStream(socket.getInputStream());
            String str = dataInputStream.readUTF();
            System.out.println(str);
            dataInputStream.close();
            socket.close();
            System.out.println("end");
        } catch (IOException e1) {
            e1.printStackTrace();
        }
    }

}

类Client.java：

import java.io.*;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client {
    public static void main(String[] args) {
        try {
            System.out.println("client connecting...");
            byte[] addr = {(byte) 192, (byte) 168, (byte) 9, (byte) 9};
            InetAddress inetAddress = InetAddress.getByAddress("lvh", addr);
            Socket socket = new Socket(inetAddress, 6667);
            //socket.setSoTimeout(999999999);
            System.out.println(socket.isConnected());
            DataOutputStream dataOutputStream = new DataOutputStream(socket.getOutputStream());
            dataOutputStream.writeUTF("hello");
            dataOutputStream.flush();
            dataOutputStream.close();
            socket.close();
            System.out.println("end");
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

我将类 Client.java 发送到其他 PC 并收到错误“连接超时”，如下图 (T_T)： enter image description here

我不知道如何解决 :((请帮忙！！！

【问题讨论】：

标签： java sockets server connection client

【解决方案1】：

在打开DataInputStream之前，需要在两端打开DataOutputStream。

更新：添加代码

服务器.java

package src;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {

    public static void main(String[] args) throws IOException {
        try {
            System.out.println("loading..");
            ServerSocket serverSocket = new ServerSocket(6667);
            try (Socket socket = serverSocket.accept()) {
                try (DataOutputStream dataOutputStream = new DataOutputStream(socket.getOutputStream())) {
                    try (DataInputStream dataInputStream = new DataInputStream(socket.getInputStream())) {
                        String str = dataInputStream.readUTF();
                        System.out.println(str);
                    }
                }
            }
            System.out.println("end");
        } catch (IOException e1) {
            e1.printStackTrace();
        }
    }

}

客户端.java

package src;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.InetAddress;
import java.net.Socket;

public class Client {
    public static void main(String[] args) {
        try {
            System.out.println("client connecting...");
            byte[] addr = {(byte) 127, (byte) 0, (byte) 0, (byte) 1};
            InetAddress inetAddress = InetAddress.getByAddress("localhost", addr);
            try (Socket socket = new Socket(inetAddress, 6667)) {
                //socket.setSoTimeout(999999999);
                System.out.println(socket.isConnected());
                try (DataOutputStream dataOutputStream = new DataOutputStream(socket.getOutputStream())) {
                    try (DataInputStream dataInputStream = new DataInputStream(socket.getInputStream())) {
                        dataOutputStream.writeUTF("hello");
                    }
                }
            }
            System.out.println("end");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

服务器输出

loading..
hello
end

客户端输出：

client connecting...
true
end

希望这会有所帮助。 :)

【讨论】：