如何通过servlet批量提供文件下载？

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class FileDownloadServlet extends HttpServlet {

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 获取要下载的文件路径或文件对象
        String[] fileNames = {"file1.txt", "file2.txt", "file3.txt"}; // 假设要下载的文件名数组
        String zipFileName = "download.zip"; // 压缩文件名

        // 设置响应头信息
        response.setContentType("application/octet-stream");
        response.setHeader("Content-Disposition", "attachment;filename=" + zipFileName);

        // 创建压缩文件的输出流
        ZipOutputStream zipOut = new ZipOutputStream(response.getOutputStream());

        // 将每个文件依次写入压缩文件
        for (String fileName : fileNames) {
            File file = new File(fileName);
            FileInputStream fis = new FileInputStream(file);
            ZipEntry zipEntry = new ZipEntry(file.getName());
            zipOut.putNextEntry(zipEntry);

            byte[] buffer = new byte[1024];
            int len;
            while ((len = fis.read(buffer)) > 0) {
                zipOut.write(buffer, 0, len);
            }

            fis.close();
        }

        // 关闭输出流
        zipOut.close();

    }
}