J2EE中EL和JSTL结合运用
这里的例子只是简单的Servlet+JSP，没有用到框架，如果用到Struts的话，只要符合Struts中Action标准，或者直接用Struts标签替代就可以了。
ToMainAction
public class ToMainAction extends HttpServlet
{
private IBoarderDao boardDao = new BoardDaoImpl();
private ITopicDao topicDao = new TopicDaoImpl();
private IUserDao userDao = new UserDaoImpl();
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
// 板块列表
List<Board> boards = boardDao.getAllBoard();
List<Integer> count = new ArrayList<Integer>();
List<User> users = new ArrayList<User>();
List<Topic> lastTopic = new ArrayList<Topic>();
if (null != boards)
{
for (Board b : boards)
{
// 回帖数
List<Topic> topic = topicDao.getTopicByBoardId(b.getBorderId());
if (null != topic)
{
int num = topic.size();
count.add(num);
}
else
{
count.add(0);
}
// 最近更新
Topic t = topicDao.getLastTopic(b.getBorderId());
lastTopic.add(t);
// 最近更新的作者
User u = userDao.getUserByuId(t.getUid());
users.add(u);
}
request.setAttribute("boards", boards);
request.setAttribute("count", count);
request.setAttribute("users", users);
request.setAttribute("lastTopic", lastTopic);
RequestDispatcher dis = request.getRequestDispatcher("main.jsp");
dis.forward(request, response);
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
this.doGet(request, response);
}
}
main.jsp
<body>
<div id="container">
<div id="divlogin">
<jsp:include page="checUser.jsp"></jsp:include>
</div>
<div class="nav">
<div align="left" style="font-weight: bold"></div>
</div>
<table width="100%" border="3" bordercolor="#D0E3FF"
style="font-size: 12px">
<tr style="background-color: #F3F8EF">
<td height="22" colspan="2" class="noborder">
</td>
<td width="11%" style="border: 0; font-size: 12px">
发帖数
</td>
<td width="21%" style="border: 0; font-size: 12px">
最近更新
</td>
</tr>
<c:if test="${requestScope.boards!=null}">
<c:forEach var="b" items="${requestScope.boards}" varStatus="status">
<tr>
<td width="6%" height="68">
</td>
<td width="67%">
<div align="left" class="blueSpan">
<img src="images/topic.gif" width="18" height="21" />
<a href="ToListAction?boardId=${b.borderId}">${b.borderName}</a>
</div>
</td>
<td>
${requestScope.count[status.index]}
</td>
<td>
<br />
<p align="left">
${requestScope.lastTopic[status.index].title}
</p>
<br />
<p align="left">
${requestScope.users[status.index].userName}
</p>
<br />
<p align="left">
修改时间：
<br>
${requestScope.lastTopic[status.index].modifyTime}
</p>
</td>
</tr>
</c:forEach>
</c:if>
</table>
<div id="divCopy">
© xy制作—2011-09-01
</div>
</div>
</body>
checUser.jsp
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<c:if test="${not empty sessionScope.uinfo}">
<span style="color: blue">欢迎您：${sessionScope.uinfo.userName} </span>
<span style="color: blue"><a href="GoBackAction">退出</a> </span>
</c:if>
<c:if test="${empty sessionScope.uinfo}">
<span style=""><a href="ToLoginAction">登录</a></span>
</c:if>