Question

我正在开发一个简单的JSP-Servlet-Hibernate应用程序。我已经成功使用Hibernate检索了数据。在jsp页面上设置相同的值（从Servlet检索）时，我遇到了问题。

我尝试过表达语言。但它不起作用。我不知道为什么它不起作用。

Servlet代码：：

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        User user=new User();
        user.setUserId(Integer.parseInt(request.getParameter("Id")));
        user.setUserName(request.getParameter("name"));
        user.setUserEmail(request.getParameter("email"));
        user.setUserPhone(request.getParameter("number"));
        HibernateTest ht=new HibernateTest();
        User user2= ht.saveDetails(user);
        //fileRead();
        RequestDispatcher rd=request.getRequestDispatcher("index.jsp");
        rd.include(request, response);
        request.setAttribute("user", user2);
        System.out.println(user2.getUserId());
        response.setContentType("text/html");
        PrintWriter pw=response.getWriter();
        pw.println("Saved successful and retrieve successful..............."+ ((User)request.getAttribute("user")).getUserId());
    }

jsp页面：

<form action="FirstServlet" method="post">
<table border="1">
<tr>
<td>User Id:</td>
<td><input type="text" name="Id" value="${reqestScope.user.userId}"/></td><!-- it remains blank at retrieval time -->
</tr>
<tr>
<td>User Name:</td>
<td><input type="text" name="name" value="${reqestScope.user.userName}" /></td><!-- it remains blank at retrieval time -->
</tr>
<tr>
<td>User Email:</td>
<td><input type="text" name="email" value="${reqestScope.user.userEmail}"/></td><!-- it remains blank at retrieval time -->
</tr>
<tr>
<td>Phone Number:</td>
<td><input type="text" name="number" value="${reqestScope.user.userPhone}"/></td><!-- it remains blank at retrieval time -->
</tr>
<tr><td colspan="2"><input type="submit" value="Submit"/></tr>
</table>
</form>
<% 
if(((User)request.getAttribute("user"))!=null)
    System.out.println(((User)request.getAttribute("user")).getUserId()); %><!-- it prints the correct result.. -->

从Servlet类检索的值应正确显示在jsp页面上。但实际上，在检索时它仍然是空白的。

Answer 1

您应该尝试正确纠正requestScope（您写了reqest），如果它不起作用，请使用JSTL进行尝试，所以不要使用：

<input type="text" name="Id" value="${requestScope.user.userId}"/>

您应该尝试：

<input type="text" name="Id" value="<c:out value="${requestScope.user.userId}"/>" >

无法在从Servlet检索的JSP页面中设置值

1 个答案: