编写基于TCP的网络应用程序 【要求】 实现客户端和服务器端的双向数据传输。两人一组完成测试。用Java程序编写

好的，我可以为你提供一份基于Java语言编写的基于TCP的网络应用程序示例。代码如下：

服务器端代码：

import java.io.*;
import java.net.*;

public class TCPServer {
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = null;
        try {
            serverSocket = new ServerSocket(8888);
        } catch (IOException e) {
            System.err.println("Could not listen on port: 8888.");
            System.exit(1);
        }

        Socket clientSocket = null;
        try {
            System.out.println("Waiting for connection.....");
            clientSocket = serverSocket.accept();
            System.out.println("Connection established with: " + clientSocket.getInetAddress().getHostName());
        } catch (IOException e) {
            System.err.println("Accept failed.");
            System.exit(1);
        }

        PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
        BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
        BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));

        String inputLine;

        while ((inputLine = in.readLine()) != null) {
            System.out.println("Client: " + inputLine);
            out.println(stdIn.readLine());
        }

        out.close();
        in.close();
        stdIn.close();
        clientSocket.close();
        serverSocket.close();
    }
}

客户端代码：

import java.io.*;
import java.net.*;

public class TCPClient {
    public static void main(String[] args) throws IOException {

        Socket echoSocket = null;
        PrintWriter out = null;
        BufferedReader in = null;
        BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));

        try {
            echoSocket = new Socket("localhost", 8888);
            out = new PrintWriter(echoSocket.getOutputStream(), true);
            in = new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));
        } catch (UnknownHostException e) {
            System.err.println("Don't know about host: localhost.");
            System.exit(1);
        } catch (IOException e) {
            System.err.println("Couldn't get I/O for the connection to: localhost.");
            System.exit(1);
        }

        String userInput;

        while ((userInput = stdIn.readLine()) != null) {
            out.println(userInput);
            System.out.println("Server: " + in.readLine());
        }

        out.close();
        in.close();
        stdIn.close();
        echoSocket.close();
    }
}

这里我们以服务端监听本地的8888端口，客户端连接localhost的8888端口为例。建立连接后，双方可进行数据传输，每次客户端发送数据后，服务端会返回一条信息。

你可以在两台计算机上分别运行以上代码，尝试进行双向数据传输的测试。