java实现大文件上传下载HTTP接口代码实现

很高兴为您解答。以下是 Java 实现大文件上传下载 HTTP 接口的示例代码：

文件上传

public class FileUploadHandler extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String savePath = "C:/uploads";
        String tempPath = "C:/uploads/temp";
        File tempFile = new File(tempPath);
        if (!tempFile.exists()) {
            tempFile.mkdir();
        }
        DiskFileItemFactory factory = new DiskFileItemFactory();
        factory.setSizeThreshold(1024 * 1024);
        factory.setRepository(tempFile);
        ServletFileUpload upload = new ServletFileUpload(factory);
        upload.setHeaderEncoding("UTF-8");
        try {
            List<FileItem> items = upload.parseRequest(request);
            for (FileItem item : items) {
                if (item.isFormField()) {
                    continue;
                }
                String fileName = item.getName();
                long fileSize = item.getSize();
                if ("".equals(fileName) || fileSize == 0) {
                    continue;
                }
                int index = fileName.lastIndexOf(".");
                String fileType = fileName.substring(index + 1);
                String newFileName = UUID.randomUUID().toString() + "." + fileType;
                String saveFilePath = savePath + "/" + newFileName;
                File saveFile = new File(saveFilePath);
                item.write(saveFile);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

文件下载

public class FileDownloadHandler extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String fileName = request.getParameter("fileName");
        String filePath = "C:/uploads/" + fileName;
        File file = new File(filePath);
        if (!file.exists()) {
            return;
        }
        InputStream in = new FileInputStream(file);
        OutputStream out = response.getOutputStream();
        response.setContentType("application/x-download");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
        byte[] buffer = new byte[1024];
        int len = 0;
        while ((len = in.read(buffer)) != -1) {
            out.write(buffer, 0, len);
        }
        in.close();
        out.close();
    }
}

以上代码仅供参考，具体实现可能需要根据实际情况进行调整。希望能够帮助到您！