我已经看到了类似于此问题的其他问题,但没有一个问题帮助我解决了我的问题.基本上,我正在尝试将变量从servlet传递给JSP.
servlet代码.
package com.servlets;
import java.io.IOException;
import java.util.ArrayList;
import javax.servlet.annotation.WebServlet;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.dao.DataGetter;
@WebServlet("/DataGetterServlet")
public class DataGetterServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
ArrayList<String[]> data;
private DataGetter dg;
public void init() throws ServletException {
try {
dg = new DataGetter();
data = dg.getData();
} catch (Exception e) {
throw new ServletException("An exception occurred in DataGetterServlet: "
+ e.getClass().getName());
}
}
protected void doGet(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException {
request.setAttribute("data",data);
RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
rd.forward(request,response);
}
}
我的JSP代码
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<Meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Data extractor</title>
</head>
<body>
Data table:
<table boder="1">
<c:forEach var="item" items="${data}" >
<tr>
<c:forEach var="column" items="${item}">
<td>${column}</td>
</c:forEach>
</tr>
</c:forEach>
</table>
</body>
</html>
我已经使用forEach标签完成了一些测试,并正确设置了JSTL.我认为变量“data”没有到达JSP.知道为什么吗？
提前致谢.
编辑：澄清porpuses.我试过了
<c:forEach var="i" begin="1" end="5">
Item <c:out value="${i}"/><p>
</c:forEach>
这有效,但是
<c:forEach var="item" items="${data}">
It worked!<p>
</c:forEach>
不起作用.这使我相信可变数据由于某种原因没有到达JSP.
编辑2：为了运行它,我在Eclipse上配置了一个Tomcat服务器.我右键单击servlet并选择Run As – >在服务器上运行.服务器重新启动,我从浏览器启动http：// localhost：8080 / DataExtractor /.这是生成的html：
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<Meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Data extractor</title>
</head>
<body>
Data table:
<table border="1">
</table>
</body>
</html>
编辑3：这可能是发生这种情况的关键.当我转到http：// localhost：8080 / DataExtractor /(index.jsp)时,我得到了在Edit 2中发布的html,但如果我转到http：// localhost：8080 / DataExtractor / DataGetterServlet那么我确实得到了右页！知道为什么吗？
