JSP使用当前用户的数据

Question

所以我尝试做的是让另一个JSP来获取刚刚登录的用户的信息(例如，只显示刚刚登录的特定用户的信息，而不是显示数据库中的所有内容，这与SELECT * username= user WHERE current user含义相同)。不管怎样，下面是我的代码，非常感谢！

<%  
    String userId = request.getParameter("user_id");
    String pwd = request.getParameter("password");
%>
<jsp:useBean id="db" class="ecom.DBConnection" scope="session" />
<jsp:useBean id="user" class="ecom.UserInfo" scope="session" />
<%
Connection conn = db.getConnection(); 

PreparedStatement pstmt = conn.prepareStatement(
    "select * from USERS where user_id=? and password=?");

pstmt.setString(1, userId);
pstmt.setString(2, pwd);    

ResultSet rs = pstmt.executeQuery();    


/* Comment  
    Set the user bean properties if login is successful */
if (rs.next()) {
    user.setLoggedIn(true);
    user.setUserId(rs.getString("user_id"));

} else {
    user.setLoggedIn(false);
}   

rs.close();
pstmt.close();


/* Comment 
    Forward the request to "home.jsp" if login is successful,
    otherwise forward to "error.jsp". */
String forwardURL = null;   
if (user.isLoggedIn()) {
    forwardURL = "home.jsp";
} else {
    forwardURL = "error.jsp";
} 
%>

<jsp:forward page="<%= forwardURL %>" />

这是我正在处理的页面(Setting.jsp)

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>


<jsp:useBean id="user" class="ecom.UserInfo" scope="session" />

<c:if test='${not user.loggedIn}'>
 <jsp:forward page='error.jsp'/>
</c:if>


<html>

<head>
<link href="style.css" rel="stylesheet" type="text/css"></link>
<title>Jonathan's Auction Site</title>
</head>


<body marginwidth="0" marginheight="0" leftmargin="0" rightmargin="0"    topmargin="0" bottommargin="0">

<table border="0" cellpadding="0" cellspacing="0" width="100%">
    <tr>
        <td bgcolor="#000000">Jonathan's Auction Site</td>
    </tr>

    <tr>
        <td bgcolor="#cccccc" height="18" class="menu">
        <font color="#ffffff">|</font> <B><a class="menu" href="home.jsp">Home</a></B>
        <font color="#ffffff">|</font> <B><a class="menu" href="register.jsp">Register</a></B>
        <font color="#ffffff">|</font> <B><a class="menu" href="Post.jsp">Post Items</a></B>
        <font color="#ffffff">|</font> <B><a class="menu" href="browseItems.jsp">Browse Items</a></B>
        <font color="#ffffff">|</font> <B><a class="menu" href="manageItems.jsp">Manage Items</a></B>
        <font color="#ffffff">|</font> <B><a class="menu" href="setting.jsp">Account Settings</a></B>
        <font color="#ffffff">|</font> <B><a class="menu" href="logout.jsp">Logout</a></B>
        <font color="#ffffff">|</font>
        </td>
    </tr>
</table>


<%@ taglib prefix='sql' uri='http://java.sun.com/jsp/jstl/sql' %>

<sql:setDataSource 
        driver='com.mysql.jdbc.Driver'
        url='jdbc:mysql://************'
        user='USER'
        password='Password'
        var='030'
        scope='session'
/>      


<%
String userId = request.getParameter("user_id");
%>

<sql:query dataSource='${030}' var='USERS'>
SELECT * FROM USERS
</sql:query>


<table width="63%" border="0">
  <tr> 
    <td width="16%" height="46">&nbsp;</td>
    <td width="73%" height="46"> 
      <p>&nbsp;</p>
      </td>
    <td width="11%" height="46">&nbsp;</td>
  </tr>


<c:forEach var='USERS' items='${USERS.rows}'>

  <tr> 
    <td width="16%">&nbsp;</td>
    <td width="73%"> 
        <table width="352" border="1">
            <tr>
                <td>
                    <h3>${USERS.user_id}</h3>
                </td>
            </tr>
      </table>
      </form>   
    </td>
    <td width="11%">&nbsp;</td>
  </tr>
  <tr> 
    <td width="16%">&nbsp;</td>
    <td width="73%">&nbsp;</td>
    <td width="11%">&nbsp;</td>
  </tr>

</c:forEach>


  <tr> 
    <td width="16%">&nbsp;</td>
    <td width="73%">&nbsp;</td>
    <td width="11%">&nbsp;</td>
  </tr>
  <tr> 
    <td width="16%">&nbsp;</td>
    <td width="73%" align="center">&nbsp;</td>
    <td width="11%">&nbsp;</td>
  </tr>

</table>
<p>&nbsp;</p>
</body>

</html>

(现在它会显示数据库中的所有用户名，但我只想要一个与登录的用户名相同的用户名)

Answer 1

看起来你需要在这里修改Setting.jsp：

<sql:query dataSource='${030}' var='USERS'>
SELECT * FROM USERS
</sql:query>

如果唯一的问题是它列出了您的所有用户，而不是会话中的用户，那么添加WHERE USER.ID = ? (或您的id列)并将其注册为一个参数，类似于您的工作JSP：

PreparedStatement pstmt = conn.prepareStatement(
    "select * from USERS where user_id=?");

pstmt.setString(1, userId);