从数据库中检索表：javax.el.PropertyNotFoundException
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【中文标题】从数据库中检索表：javax.el.PropertyNotFoundException【英文标题】：Retrieving a table from database: javax.el.PropertyNotFoundException 【发布时间】：2013-11-26 10:45:43 【问题描述】：我想从数据库中检索整个表并将其显示到我的 jsp 页面中，但出现错误
我的 StaffBean。 java是
package com.staff.bean;
import java.util.Date;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
public class StaffBean
private String date;
private int workload;
private int hourId;
private int daysId;
private int staffId;
private String StaffName;
private String ActiveORInactive;
private String Stafftype;
private String subcode;
private boolean valid = false;
public String getdate()
// DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
// Date date = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd"); // your template here
java.util.Date dateStr = null;
try
dateStr = formatter.parse(date);
catch (ParseException e)
// TODO Auto-generated catch block
e.printStackTrace();
java.sql.Date dateDB = new java.sql.Date(dateStr.getTime());
return formatter.format(dateDB);
public void setdate(String date)
this.date=date;
public int gethourId()
return hourId;
public void sethourId(int hourId)
this.hourId = hourId;
public int getdaysId()
return daysId;
public void setdaysId(int daysId)
this.daysId = daysId;
public int getworkload()
return hourId;
public void setworkload(int workload)
this.workload = workload;
public int getstaffId()
return staffId;
public void setstaffId(int staffId)
this.staffId = staffId;
public String getStaffName()
return StaffName;
public void setStaffName(String StaffName)
this.StaffName = StaffName;
public String ActiveORInactive()
return ActiveORInactive;
public void setActiveORInactive(String ActiveORInactive)
this.ActiveORInactive = ActiveORInactive;
public String getStafftype()
return Stafftype;
public void setStafftype(String Stafftype)
this.Stafftype = Stafftype;
public String getsubcode()
return Stafftype;
public void setsubcode(String subcode)
this.subcode = subcode;
public boolean isValid()
return valid;
public void setValid(boolean valid)
this.valid = valid;
我的 GetAllDetailDAO.java 是
package com.staff.DAO;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import com.staff.bean.StaffBean;
import com.staff.DB.ConnectionProvider;
public class GetAllDetailDAO
Connection con;
Statement stmt;
private int noOfRecords;
public List<StaffBean> viewAllStaff(int offSet, int noOfRecords)
List<StaffBean> list = new ArrayList<StaffBean>();
StaffBean _staffBean;
try
con = ConnectionProvider.getConnection();
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("select SQL_CALC_FOUND_ROWS * from tblstaffdetails limit "+offSet+","+noOfRecords);
//+offSet+","+noOfRecords);
//SQL_CALC_FOUND_ROWS
while(rs.next())
_staffBean = new StaffBean();
_staffBean.setStaffName(rs.getString("StaffName"));
_staffBean.setstaffId(rs.getInt("staffId"));
_staffBean.setActiveORInactive(rs.getString("ActiveORInactive"));
_staffBean.setStafftype(rs.getString("Stafftype"));
list.add(_staffBean);
rs.close();
rs = stmt.executeQuery("SELECT FOUND_ROWS()");
if(rs.next())
this.noOfRecords = rs.getInt(1);
catch (SQLException e)
// TODO Auto-generated catch block
e.printStackTrace();
return list;
public int getNoOfRecords()
return noOfRecords;
连接提供者 包 com.staff.DB;
import java.sql.*;
public class ConnectionProvider
static Connection con;
static String url;
public static Connection getConnection() throws SQLException
try
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/StaffAllocation","root", "success");
catch(ClassNotFoundException cnf)
cnf.printStackTrace();
return con;
而我的 GetAllDetailServlet.java 是
package com.staff.servlet;
import java.io.IOException;
import java.util.List;
import java.sql.*;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.staff.bean.StaffBean;
import com.staff.DAO.GetAllDetailDAO;
import com.staff.DB.*;
@WebServlet("/GetAllDetailServlet")
public class GetAllDetailServlet extends HttpServlet
/**
* Servlet implementation class GetAllDetailsServlet
*/
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public GetAllDetailServlet()
super();
// TODO Auto-generated constructor stub
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
// TODO Auto-generated method stub
int page = 1;
int recordsPerPage = 4;
if(request.getParameter("page") != null)
page = Integer.parseInt(request.getParameter("page"));
GetAllDetailDAO allDetailDAO = new GetAllDetailDAO();
List<StaffBean> list = allDetailDAO.viewAllStaff((page-1)*recordsPerPage, recordsPerPage);
int noOfRecords = allDetailDAO.getNoOfRecords();
int noOfPages = (int) Math.ceil(noOfRecords * 1.0 / recordsPerPage);
request.setAttribute("staffList", list);
request.setAttribute("noOfPages", noOfPages);
request.setAttribute("currentPage", page);
RequestDispatcher view = request.getRequestDispatcher("jsp/displayAllDetail.jsp");
view.forward(request, response);
我的 DisplayAllDetail.jsp 是
<html>
<head>
<link rel="stylesheet" type="text/css" href="css/style.css"/>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title> :: All Details</title>
</head>
<body>
<fieldset>
<table border="1" cellpadding="4" cellspacing="4" align="center">
<tr>
<th>staffId</th>
<th>StaffName</th>
<th>ActiveORInactive</th>
<th>Stafftype</th>
<c:forEach var="_staffBean" items="$staffList">
<tr>
<td>$_staffBean.staffId</td>
<td>$_staffBean.StaffName</td>
<td>$_staffBean.ActiveORInactive</td>
<td>$_staffBean.Stafftype</td>
</tr>
</c:forEach>
</tr>
</table>
<c:if test="$currentPage != 1">
<td><a href="getAll.do?method=get&page=$currentPage - 1">Prev</a></td>
</c:if>
<table border="1" cellpadding="5" cellspacing="5" align="center">
<tr>
<c:forEach begin="1" end="$noOfPages " var="i">
<c:choose>
<c:when test="$currentPage eq i ">
<td>$i</td>
</c:when>
<c:otherwise>
<td><a href="getAll.do?method=get&page=$i">$i</a></td>
</c:otherwise>
</c:choose>
</c:forEach>
</tr>
</table>
<c:if test="$currentPage lt noOfPages ">
<td><a href="getAll.do?method=get&page=$currentPage+1 ">Next</a></td>
</c:if>
</fieldset>
</body>
</html>
我的错误是
HTTP Status 500 - An exception occurred processing JSP page /jsp/displayAllDetail.jsp at line 22
type Exception report
message An exception occurred processing JSP page /jsp/displayAllDetail.jsp at line 22
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: An exception occurred processing JSP page /jsp/displayAllDetail.jsp at line 22
19: <c:forEach var="_staffBean" items="$staffList">
20: <tr>
21: <td>$_staffBean.staffId</td>
22: <td>$_staffBean.StaffName</td>
23: <td>$_staffBean.ActiveORInactive</td>
24: <td>$_staffBean.Stafftype</td>
25: </tr>
堆栈跟踪： org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:568) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334) javax.servlet.http.HttpServlet.service(HttpServlet.java:728) com.staff.servlet.GetAllDetailServlet.doGet(GetAllDetailServlet.java:56) javax.servlet.http.HttpServlet.service(HttpServlet.java:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
根本原因
javax.el.PropertyNotFoundException: Property 'StaffName' not found on type com.staff.bean.StaffBean
javax.el.BeanELResolver$BeanProperties.get(BeanELResolver.java:237)
javax.el.BeanELResolver$BeanProperties.access$400(BeanELResolver.java:214)
javax.el.BeanELResolver.property(BeanELResolver.java:325)
javax.el.BeanELResolver.getValue(BeanELResolver.java:85)
org.apache.jasper.el.JasperELResolver.getValue(JasperELResolver.java:104)
org.apache.el.parser.AstValue.getValue(AstValue.java:183)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:185)
org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:1026)
org.apache.jsp.jsp.displayAllDetail_jsp._jspx_meth_c_005fforEach_005f0(displayAllDetail_jsp.java:157)
org.apache.jsp.jsp.displayAllDetail_jsp._jspService(displayAllDetail_jsp.java:99)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
com.staff.servlet.GetAllDetailServlet.doGet(GetAllDetailServlet.java:56)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
注意 Apache Tomcat/7.0.42 日志中提供了根本原因的完整堆栈跟踪。
【问题讨论】：
不要在标题中寻求帮助 - 在这里提出问题的每个人都希望得到答案。 在 getdate() 中，您将日期字符串解析为日期，然后再次将其格式化回字符串？？？？我真的不认为你想那样做！ NickJ，请帮我解决我的错误。我想检索一个表格并显示它，你能帮忙吗？ 请用您所做的代码更改更新您的问题。我看不出还有什么问题。 我没有做太多的改变。唯一的问题是表格没有显示出来。 【参考方案1】：尝试声明
private String staffName;
private String activeORInactive;
private String stafftype;
而不是大写字母。
建议你关注Java Code convertions
【讨论】：
但是我已经创建了以大写字母开头的列的名称。如果我将它们编辑成更小的大小写会有什么变化？ 你是如何映射你的数据库的？你在使用 OpenJpa，Hibernate 吗？如何初始化 ConnectionProvider？ 对不起.. 我现在将我的连接提供商包括在我的问题中 我假设您使用的是 Hibernate。 JavaObject 属性名和列名彼此无关。只有你正在使用的映射（主要是 Hibernate 的 porpuse，让你忘记数据库名称，只使用面向对象的编程）在你的 java 对象中，你应该遵循约定，js 不会有问题 如果你是编程的初学者，并且你正在使用 Hibernate，我会劝阻你。 Hibernate 只适合高级程序员。我建议你改为学习 JDBC。【参考方案2】：在 Blanca Hdez 的正确答案的基础上，更改 JSP，使 staffName 的大小写正确：
<td>$_staffBean.StaffName</td>
应该是：
<td>$_staffBean.staffName</td>
注意“staffName”的小写“s”——非常重要！
【讨论】：
你是否也听从了布兰卡·赫德兹的建议？ 是的。我试着转换成小写字母。请检查我的jsp页面。错误在于说明 c:forEach var="_staffBean" items="$staffList" 应该赋予var什么值？必须用 _staffBean 替换什么以上是关于从数据库中检索表：javax.el.PropertyNotFoundException的主要内容，如果未能解决你的问题，请参考以下文章