TCP通信练习3--上传文件 客户端：将本地文件上传到服务器。接收服务器的反馈。 服务器：接收客户端上传的文件，上传完毕之后给出反馈。完整代码

在Java中，使用TCP进行文件上传通常涉及到Socket编程，这里我会提供一个简单的客户端和服务器端的基本示例。请注意，这只是一个基础的例子，实际应用中可能需要考虑错误处理、文件分块传输等复杂情况。

**服务器端（Server.java）：**

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

public class Server {
    private static final int PORT = 8080; // 设置监听端口

    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = new ServerSocket(PORT);
        System.out.println("Server started on port " + PORT);

        while (true) {
            Socket clientSocket = serverSocket.accept();
            handleClient(clientSocket);
        }
    }

    private static void handleClient(Socket socket) {
        try (BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
             PrintWriter out = new PrintWriter(socket.getOutputStream(), true)) {

            String fileName = "";
            System.out.print("Enter file name to upload: ");
            fileName = in.readLine();

            File file = new File(fileName);
            if (!file.exists()) {
                out.println("File not found");
            } else {
                FileInputStream fis = new FileInputStream(file);
                byte[] buffer = new byte[(int) file.length()];
                int bytesRead;
                while ((bytesRead = fis.read(buffer)) != -1) {
                    out.write(buffer, 0, bytesRead);
                }
                fis.close();
                out.println("File uploaded successfully");
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

**客户端（Client.java）：**

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

public class Client {
    private static final String SERVER_ADDRESS = "localhost"; // 服务器地址
    private static final int PORT = 8080;

    public static void main(String[] args) throws IOException {
        Socket socket = new Socket(SERVER_ADDRESS, PORT);
        System.out.println("Connected to server");

        BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        PrintStream out = new PrintStream(socket.getOutputStream());

        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the file path to be uploaded: ");
        String filePath = scanner.nextLine();
        File file = new File(filePath);
        if (file.exists()) {
            FileInputStream fis = new FileInputStream(file);
            byte[] fileContent = new byte[(int) file.length()];
            fis.read(fileContent);
            out.write(fileContent);
            out.flush();
            System.out.println("Sending file...");
            System.out.println("Sent file. Waiting for response...");

            String response = in.readLine();
            if (response.equals("File uploaded successfully")) {
                System.out.println("Upload successful!");
            } else {
                System.out.println(response);
            }
        } else {
            out.println("File not found");
        }
    }
}

**运行说明：**
1. 首先在服务器上运行`Server.java`。
2. 在客户端运行`Client.java`，并按照提示输入要上传的文件路径。

**相关问题--:**
1. TCP是如何支持文件上传的？
2. 上述代码中的`accept()`方法在服务器端有什么作用？
3. 客户端如何确定文件已经成功上传？
4. 如何在实际环境中防止文件过大导致传输失败？