在地图上迭代并在jsp中显示
我必须在页面中显示对象的地图 Struts操作类如下所示:在地图上迭代并在jsp中显示,jsp,struts,Jsp,Struts,我必须在页面中显示对象的地图 Struts操作类如下所示: public class DonorListAction extends Action{ public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpSer
public class DonorListAction extends Action{
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request,
HttpServletResponse response) throws Exception
{
DonorDAO donorDAO = new DonorDAO();
HashMap<Integer, DonorDetailsForm> donorMap =donorDAO.getDonorList();
request.setAttribute("donorMap",donorMap);
return mapping.findForward("success");
}
}
<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean"%>
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html"%>
<%@ taglib uri="http://struts.apache.org/tags-logic" prefix="logic"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
公共类DonorListAction扩展操作{
公共ActionForward执行(ActionMapping映射、ActionForm表单、,
HttpServletRequest请求,
HttpServletResponse)引发异常
{
DonorDAO DonorDAO=新DonorDAO();
HashMap donorMap=donorDAO.getDonorList();
setAttribute(“donorMap”,donorMap);
返回映射。findForward(“成功”);
}
}
jsp页面如下所示:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<%@ page language="java"%>
<%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean"%>
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html"%>
<%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic"%>
<%@ taglib uri="/WEB-INF/c.tld" prefix="c"%>
<html>
<HEAD><TITLE>List of Donors</TITLE></HEAD>
<body BGCOLOR="#FDF5E6">
<table align="center" border="1">
<tr>
<th align="center">Donor ID</th>
<th align="center">Name</th>
<th align="center">Email Address</th>
<th align="center">Phone Number</th>
</tr>
<c:forEach var="donor" items="${donorMap}">
<tr>
<td align="right">${donor.key}</td>
<td align="right">${donor.value.firstName} ${donor.value.lastName}</td>
<td align="right">${donor.value.emailAddress}</td>
<td align="right">${donor.value.phoneNumber}</td>
</tr>
</c:forEach>
</table>
</body>
</html>
捐助者名单
捐赠者ID
名称
电子邮件地址
电话号码
${provider.key}
${donor.value.firstName}${donor.value.lastName}
${donor.value.emailAddress}
${donor.value.phoneNumber}
现在,当我执行此代码时,我得到:
javax.el.PropertyNotFoundException: Property 'key' not found on type java.lang.String
javax.el.BeanELResolver$BeanProperties.get(BeanELR esolver.java:193)
javax.el.BeanELResolver$BeanProperties.access$400( BeanELResolver.java:170)
javax.el.BeanELResolver.property(BeanELResolver.ja va:279)
javax.el.BeanELResolver.getValue(BeanELResolver.ja va:60)
javax.el.CompositeELResolver.getValue(CompositeELR esolver.java:54)
org.apache.el.parser.AstValue.getValue(AstValue.ja va:118)
org.apache.el.ValueExpressionImpl.getValue(ValueEx pressionImpl.java:186)
org.apache.jasper.runtime.PageContextImpl.propriet aryEvaluate(PageContextImpl.java:925)
org.apache.jsp.jsp.DisplayDonorList_jsp._jspx_meth _c_005fforEach_005f0(DisplayDonorList_jsp.java:121 )
org.apache.jsp.jsp.DisplayDonorList_jsp._jspServic e(DisplayDonorList_jsp.java:83)
org.apache.jasper.runtime.HttpJspBase.service(Http JspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet .java:717)
org.apache.jasper.servlet.JspServletWrapper.servic e(JspServletWrapper.java:369)
org.apache.jasper.servlet.JspServlet.serviceJspFil e(JspServlet.java:322)
org.apache.jasper.servlet.JspServlet.service(JspSe rvlet.java:249)
javax.servlet.http.HttpServlet.service(HttpServlet .java:717)
org.apache.struts.action.RequestProcessor.doForwar d(RequestProcessor.java:1063)
org.apache.struts.action.RequestProcessor.processF orwardConfig(RequestProcessor.java:386)
org.apache.struts.action.RequestProcessor.process( RequestProcessor.java:229)
org.apache.struts.action.ActionServlet.process(Act ionServlet.java:1194)
org.apache.struts.action.ActionServlet.doGet(Actio nServlet.java:414)
javax.servlet.http.HttpServlet.service(HttpServlet .java:617)
javax.servlet.http.HttpServlet.service(HttpServlet .java:717)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doF ilter(ReplyHeaderFilter.java:96)
javax.el.PropertyNotFoundException:在java.lang.String类型上找不到属性“key”
javax.el.BeanELResolver$BeanProperties.get(BeanELR-esolver.java:193)
javax.el.BeanELResolver$BeanProperties.access$400(BeanELResolver.java:170)
javax.el.BeanELResolver.property(BeanELResolver.java:279)
javax.el.BeanELResolver.getValue(BeanELResolver.jaVA:60)
getValue(CompositeELR-esolver.java:54)
org.apache.el.parser.AstValue.getValue(AstValue.ja-va:118)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
org.apache.jasper.runtime.PageContextImpl.propriet aryEvaluate(PageContextImpl.java:925)
DisplayDonorList\u jsp.\u jspx\u meth\u c\u 005fforEach\u 005f0(DisplayDonorList\u jsp.java:121)
DisplayDonorList\u jsp.\u jspservice e(DisplayDonorList\u jsp.java:83)
org.apache.jasper.runtime.HttpJspBase.service(Http JspBase.java:70)
javaservlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)
org.apache.jasper.servlet.JspServlet.serviceJspFil e(JspServlet.java:322)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:249)
javaservlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.struts.action.RequestProcessor.doforward(RequestProcessor.java:1063)
org.apache.struts.action.RequestProcessor.processF orwardConfig(RequestProcessor.java:386)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:229)
org.apache.struts.action.ActionServlet.process(Act-ionServlet.java:1194)
org.apache.struts.action.ActionServlet.doGet(actionnservlet.java:414)
javaservlet.http.HttpServlet.service(HttpServlet.java:617)
javaservlet.http.HttpServlet.service(HttpServlet.java:717)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doF ilter(ReplyHeaderFilter.java:96)
我犯了什么错误?异常基本上是告诉
var
属性中保存的对象等于java.lang.String
。所以它看起来像${donorMap}
实际上是一个列表
或者可能是一个字符串[]
。另外,方法getDonorList()
表明它实际上返回的是一个列表
,而不是哈希映射
我不确定问题的根本原因,也许你没有运行你认为正在运行的代码,但是下面
<%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean"%>
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html"%>
<%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic"%>
<%@ taglib uri="/WEB-INF/c.tld" prefix="c"%>
另见:
这就是说,这种提取taglib文件的错误做法通常在roseindia.com的Struts/JSTL教程中公开。确保你没有跟随他们。即使没有,只要记住这个网站,当你不小心降落到这个网站时,立即点击
Ctrl+W
另见: