【发布时间】：2011-09-05 18:07:15
【问题描述】：
我的 JSP 给出一个错误，表明它无法在 DTO 中找到属性，但在 DTO 中该属性确实存在。以下是错误：
类型异常报告 信息 描述 服务器遇到一个内部错误 () 阻止它完成这个请求。 例外 org.apache.jasper.JasperException：在第 101 行处理 JSP 页面 /addPos.jsp 时发生异常 98: 99：--%> 100： 101：${dt.日期} 102： 103： 104： 堆栈跟踪： org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390) 根本原因 javax.el.PropertyNotFoundException：在类型 p1.dateDto 上找不到属性“日期” javax.el.BeanELResolver$BeanProperties.get(BeanELResolver.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) javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54) org.apache.el.parser.AstValue.getValue(AstValue.java:118) org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:935) org.apache.jsp.addPos_jsp._jspx_meth_c_005fforEach_005f0(addPos_jsp.java:227) org.apache.jsp.addPos_jsp._jspService(addPos_jsp.java:168) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390)这里是 dateDto 类：
package p1;
import java.sql.Date;
/**
*
* @author kk
*/
public class dateDto
{
private Date date;
public dateDto()
{
}
public dateDto(Date date)
{
this.date =date;
}
public Date getDateDto()
{
return this.date ;
}
}
下面是日期道：
package p1;
/**
*
* @author kk
*/
import java.sql.*;
import java.util.*;
public class dateDao {
private List<dateDto> dateList;
private String dbUrl = "jdbc:mysql://localhost/mvs_db";
private String dbDriver = "com.mysql.jdbc.Driver";
private String dbUser = "root";
private String dbPwd = "";
public dateDao() {
}
public List<dateDto> getDateList() {
dateList = new ArrayList<dateDto>();
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
try {//trying to load the database driver and establish a connection to the database
Class.forName(dbDriver);//loading the database driver
con = DriverManager.getConnection(dbUrl, dbUser, dbPwd);//establishing a connection to the database
//pw.println("connection established");//output if connection is established
} catch (Exception e) {
e.printStackTrace();//printing the exception error trace
}
try {
stmt = con.createStatement();
rs = stmt.executeQuery("Select vote_date from voting_date");
while (rs.next()) {
java.sql.Date date = rs.getDate("vote_date");
dateDto s = new dateDto(date);
dateList.add(s);
}
} catch (Exception e) {
System.out.println(e);
} finally {
try {
if (con != null) {
con.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return dateList;
}
}
我实际上是从 mysql 数据库中检索日期类型值并显示在下拉列表中。
JSP 代码如下：
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<jsp:useBean id="dtb" scope="session" class="p1.dateDao"/>
<%--
Document : addCamp
Created on : May 20, 2011, 11:28:31 AM
Author : ken
--%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<style type="text/css">
body {
background-color:#AFC7C7;
padding: 0;
margin: 0;
}
div.wrapper {
margin-left: 10%;
margin-right: 10%;
background-color:#6D7B8D;
height: 607px;
padding-top:0px;
border: thin solid #000000;
}
div#image{
padding-top:1%;
padding-bottom:1%;
}
div#adminlogin{
width:35%;
height:40%;
background-color:#AFC7C7;
border-width:thin;
border-style:solid;
border-color:#000000;
margin: 0 auto;
text-align:left;
overflow: hidden;
padding: 5px;
}
hr {
height:1px;
color:#000000;
background-color:#000000;
width:99%;
margin-left: 0 ;
margin-right: auto ;
border-style:solid;
}
.inputtext {
width: 200px;
height: 30px;
Font-Family:Arial;
Font-Size:18px
}
</style>
<script language="javascript" type="text/javascript">
function clearText(field){
if (field.defaultValue == field.value) field.value = '';
else if (field.value == '') field.value = field.defaultValue;
}
</script>
</head>
<body>
<div class="wrapper">
<div id="image">
<p>
<img src="${pageContext.request.contextPath}/images/logo.gif"
alt="banner"
width=100%
height="100"
/></p>
</div><!--end of image div-->
<div id=adminlogin >
<p style="text-align:center">Adding Voting Position</p>
<hr/>
<form method=POST id="pos" action="${pageContext.request.contextPath}/getPos">
<p/>
<%--The textfield for hostel name--%>
<label>Position<input type="text" id="pos" name="position" value="" class="inputtext"
onFocus="clearText(this)" onBlur="clearText(this)"/></label><br/>
<br/>
<label>Voting Date <select name="dates" size="1" id="pos" class="inputtext"
onFocus="clearText(this)" onBlur="clearText(this)">
<c:forEach items="${dtb.dateList}" var="dt">
<%--<option value="1"><c:out value="${cam.campnm}"/></option>--%>
<option>${dt.date}</option>
</c:forEach>
</select></label>
<br/>
<br/>
<input type="submit" value="Add" style="font-size:14pt; margin-left: 158px; height: 30px;"/>
</form>
<p STYLE="color : #E41B17;">${message}</p>
<c:remove var="message" scope="session" />
</div><%--end of admin login div--%>
<p style="text-align: center"><a href=adminHome.jsp>Home</a> <a href=index.jsp>Logout</a></p>
</div>
</body>
</html>
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