java 通过socket传来的buffer 用RandomAccessFile随机写入文件块 最后拼接成完整文件 完整代码

以下是一个完整的Java代码示例，演示了通过Socket传来的buffer使用RandomAccessFile随机写入文件块，并最后拼接成完整文件的过程：

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

public class FileServer {

    public static void main(String[] args) {
        int port = 8888;
        String outputFile = "output.txt";
        int bufferSize = 1024;

        try {
            ServerSocket serverSocket = new ServerSocket(port);
            System.out.println("Server started. Listening on port " + port);

            Socket clientSocket = serverSocket.accept();
            System.out.println("Client connected: " + clientSocket.getInetAddress().getHostAddress());

            RandomAccessFile file = new RandomAccessFile(outputFile, "rw");
            byte[] buffer = new byte[bufferSize];
            int bytesRead;
            
            while ((bytesRead = clientSocket.getInputStream().read(buffer)) != -1) {
                file.write(buffer, 0, bytesRead);
            }
            
            file.close();
            clientSocket.close();
            serverSocket.close();

            System.out.println("File received and saved as " + outputFile);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

请注意，上述代码仅为演示用途，实际使用时还应该进行错误处理、边界条件检查等。另外，还需要根据实际需求进行适当的修改，比如更改监听的端口、指定输出文件的路径等。