1

我已经能够将字符串和日期上传到 Mongodb,但我不知道如何使用 webapp 获取文件。

我宁愿不使用 GridFS,而是使用 byte[] 或 blob 之类的东西(但如果我必须使用 GridFS,那么我必须)。

这是我到目前为止所拥有的:

index.jsp:

<form action="./FileUploadServlet" method="POST">
    <input type="text" name="subject"/><br>
    <input type="date" name="docDate"/>
    <%--TODO: accept file into db--%>
    <input type="file" name="fileContent"/>

    <input type="submit" value="Submit">
</form>

FileUploadServlet.java:

//imports...

@WebServlet(name = "FileUploadServlet", urlPatterns = {"/FileUploadServlet"})
public class FileUploadServlet extends HttpServlet {
         throws ServletException, IOException, Exception {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            FileUploadDAO fileUploadDAO = new FileUploadDAO();
            FileUploadEntity fileUploadEntity = new FileUploadEntity();
 String subject = request.getParameter("subject");
            String dateStr = request.getParameter("docDate");
            //TODO: GET FILE CONTENTS
            Date date = new SimpleDateFormat("yyyy-MM-dd").parse(dateStr);
            fileUploadEntity.setSubject(subject);
            fileUploadEntity.setDocDate(date);
//TODO: SET FILE CONTENTS
            fileUploadDAO.persistAction(fileUploadEntity);
            response.sendRedirect("/jdc/index.jsp");
        } finally {
            out.close();
        }
    }
 @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (Exception ex) {
            Logger.getLogger(FileUploadServlet.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

我怎么把文件放在那里?我试过了

request.getParameter("fileContent");
request.getAttribute("fileContent");

但这没有用。

4

1 回答 1

1

我能够将二进制数据上传到我的数据库中,但我不确定如何检索它。这是我所拥有的:

将这些行添加到我的 processRequest 方法中:

byte[] b = request.getParameter("fileContent").getBytes();


fileUploadEntity.setFileContent(b);
于 2013-08-26T15:37:40.593 回答