如何使用Java下载文件的一部分？

import java.io.InputStream;
import java.io.OutputStream;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;

public class FileDownloader {
    public static void main(String[] args) {
        String fileUrl = "http://example.com/file.txt";
        String savePath = "C:/path/to/save/file.txt";
        int start = 0;
        int end = 1023;

        try {
            URL url = new URL(fileUrl);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestProperty("Range", "bytes=" + start + "-" + end);

            InputStream inputStream = connection.getInputStream();
            RandomAccessFile randomAccessFile = new RandomAccessFile(savePath, "rw");
            randomAccessFile.seek(start);

            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = inputStream.read(buffer)) != -1) {
                randomAccessFile.write(buffer, 0, bytesRead);
            }

            randomAccessFile.close();
            inputStream.close();
            connection.disconnect();

            System.out.println("文件下载完成！");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}