Java를 사용하여 CMS 시스템의 파일 업로드 및 다운로드 기능을 구현하는 방법

import org.apache.commons.fileupload.*; import org.apache.commons.fileupload.disk.*; import org.apache.commons.fileupload.servlet.*; // 处理文件上传的Servlet public class FileUploadServlet extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // 检查请求是否为multipart/form-data类型 boolean isMultipart = ServletFileUpload.isMultipartContent(request); if (isMultipart) { // 创建文件上传处理工厂 DiskFileItemFactory factory = new DiskFileItemFactory(); ServletContext servletContext = this.getServletConfig().getServletContext(); File repository = (File) servletContext.getAttribute("javax.servlet.context.tempdir"); factory.setRepository(repository); // 创建文件上传处理器 ServletFileUpload upload = new ServletFileUpload(factory); try { // 解析请求，获取文件项集合 List items = upload.parseRequest(request); for (FileItem item : items) { if (!item.isFormField()) { // 判断是否为文件 String fileName = item.getName(); // 获取文件名 String filePath = "文件保存路径" + fileName; // 设置文件保存路径 // 将文件保存到服务器 item.write(new File(filePath)); } } response.getWriter().write("文件上传成功！"); } catch (Exception e) { response.getWriter().write("文件上传失败：" + e.getMessage()); } } } }

public class FileDownloadServlet extends HttpServlet { protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String fileName = "要下载的文件名"; String filePath = "文件保存路径" + fileName; File file = new File(filePath); if (file.exists()) { response.setContentType("application/octet-stream"); response.setContentLength((int) file.length()); response.setHeader("Content-Disposition", "attachment; filename="" + fileName + """); try (FileInputStream fis = new FileInputStream(file); ServletOutputStream os = response.getOutputStream()){ byte[] buffer = new byte[4096]; int bytesRead = -1; while ((bytesRead = fis.read(buffer)) != -1) { os.write(buffer, 0, bytesRead); } } catch (Exception e) { response.getWriter().write("文件下载失败：" + e.getMessage()); } } else { response.getWriter().write("文件不存在！"); } } }