我的<s:iterator>标签为什么遍历不出来数据?

1,菜单主类:MainMenu,这个类定义了菜单的基本信息

/**
 * 
 */
package org.jeelee.bean;
/**
 * @author JeeLee
 *
 */
public class MainMenu {
	private String main_kind="";
	private String main_name="";
	private String main_desc="";
	private String main_pic= "";
	
	public MainMenu() {
	}
	
	/**
	 * 设置菜单主类的类别
	 * @param main_kind,String 类型
	 */
	public void setMainKind(String main_kind)
	{
		this.main_kind = main_kind ;
	}
	
	/**
	 * 获得菜单主类的类型
	 * @return 返回菜单主类的类别,String类型
	 */
	public String getMainKind()
	{
		return this.main_kind ;
	}
	
	/**
	 * 设置菜单主类的名称
	 * @param main_name,String 类型
	 */
	public void setMainName(String main_name)
	{
		System.out.println("main_name====================="+main_name);
		this.main_name = main_name ;
	}
	
	/**
	 * 获得菜单主类的ID
	 * @return 菜单主类的名称,String类型
	 */
	public String getMainName()
	{
		return this.main_name ;
	}
	
	/**
	 * 设置菜单主类的描述
	 * @param main_desc
	 */
	public void setMainDesc(String main_desc)
	{
		this.main_desc = main_desc ;
	}
	
	/**
	 * 获得菜单主类的类别描述
	 * @return
	 */
	public String getMainDesc()
	{
		return this.main_desc ;
	}
	
	/**
	 * 设置菜单主分类的图片
	 * @param pic
	 */
	public void setMainPic(String main_pic)
	{
		this.main_pic = main_pic ;
	}
	
	/**
	 * 获得菜单主分类的图片
	 * @return
	 */
	public String getMainPic()
	{
		return this.main_pic ;
	}
	

}

2.菜单主类管理 MainMenuManage ,这个类负责从数据库提取数据

/**
 * 菜单次主类管理
 */
package org.jeelee.bean;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import org.jeelee.dbmanage.DBManage;
import org.jeelee.bean.MainMenu;

/**
 * @author JeeLee
 *
 */
public class MainMenuManage {

	public MainMenuManage() {

	}
	
	DBManage dbmanage =  new DBManage();
	
	/**
	 * 获得菜单主分类,所有分类
	 * @return
	 */
	public List<MainMenu> getAllMainMenus(){
		Connection conn = null;
		Statement stm = null;
		ResultSet rs = null;
		String sql = "select main_kind, main_name, main_desc,main_pic  from mainmenu " ;
		
		List<MainMenu> mainmenuList =new ArrayList<MainMenu>();
		
		conn = dbmanage.getConnection();
		try
		{
			stm = conn.createStatement() ;
			rs = stm.executeQuery(sql);
			while(rs.next())
			{
				MainMenu myBean = new MainMenu() ;
				myBean.setMainKind(rs.getString("main_kind")) ;
				myBean.setMainName(rs.getString("main_name")) ;
				myBean.setMainDesc(rs.getString("main_desc")) ;
				myBean.setMainPic(rs.getString("main_pic"));
				System.out.println("main_kind="+rs.getString("main_kind")+",main_name="+rs.getString("main_name"));
				mainmenuList.add(myBean);
			}
		}
		catch(SQLException ex1)
		{
			System.out.println("提取主菜单失败:"+ex1);
		}
		finally
		{
			try
			{
				rs.close();
				stm.close();
				conn.close() ;
			}
			catch(SQLException ex2)
			{
				System.out.println("关闭提取主菜单失败:"+ex2);
			}
		}
		System.out.println("mainmenuList size================="+mainmenuList.size());
		return mainmenuList ;
	}
	
}

3,获取菜单的action

/**
 * 菜单主分类之action
 */
package org.jeelee.action;

import java.util.List;
import com.opensymphony.xwork2.ActionSupport;

import org.jeelee.bean.MainMenu;
import org.jeelee.bean.MainMenuManage;

/**
 * @author JeeLee
 *
 */
public class MainMenuAction extends ActionSupport {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	
	MainMenu mainMenu  ;
	List<MainMenu> mainMenus  ;
	MainMenuManage  mainMenuManage = new MainMenuManage() ;
	 
	//action 中的method
	public String list()
	{
		mainMenus = mainMenuManage.getAllMainMenus();
		System.out.println("mainMenus.size="+mainMenus.size());
		return SUCCESS ;
	}
	
	public void setMaiaMenu(MainMenu mainMenu)
	{
		this.mainMenu = mainMenu ;
	}
	
	public MainMenu getMainMenu()
	{
		return this.mainMenu ;
	}
	
	public void setMainMenus(List mainMenus){
		this.mainMenus = mainMenus ;
	} 
	
	public List getMainMenus()
	{
		return this.mainMenus ;
	}
	
	public void setMainMenuManage(MainMenuManage mainMenuManage)
	{
		this.mainMenuManage = mainMenuManage ;
	}
	
	public MainMenuManage getMainMenuManage()
	{
		return this.mainMenuManage ;
	}
	
}

4,struts.xml文件配置

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>

	<package name="jeelee" extends="struts-default">
	
    	<action name="mainMenuList" class="org.jeelee.action.MainMenuAction" method="list">
    		<result>mainmenu_list.jsp</result>
    	</action>
    	
    	<action name="personList" class="org.jeelee.action.PersonAction" method="list">
    		<result>admin/personList.jsp</result>
    	</action>
 
	</package>	
</struts>

5,JSP页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="s"  uri="/struts-tags"%>
<!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=UTF-8">
<title>main menu manage</title>
<link rel="stylesheet" rev="stylesheet" href="admin.css" type="text/css" media="all" />
<script src="resize.js" type="text/javascript"></script>
</head>

<body onload="resize()">
<s:form theme="simple">
	<div id="container" >
			<div id="title" onresize="resize()">菜单主分类管理</div>
			<table id="tab">
				<thead>
					<tr>
						<th>Row</th>
						<th><strong>菜单主分类ID</strong></th>
						<th><strong>菜单主分类名称</strong></th>
						<th><strong>菜单主分类描述</strong></th>
						<th><strong>菜单主分类图片</strong></th>
						<th><strong>修改</strong></th>
						<th><strong>删除</strong></th>
					</tr>
				</thead>
				<tbody>
					<s:iterator value="mainMenus" status="st" id="mainmenuID">
						<tr>
							<td><s:property value= '#st.index+1' /></td>
							<td><s:property value="main_kind" /></td>
							<td><s:property value="main_name" /></td>
							<td><s:property value='main_desc' /></td>
							<td><s:property value='main_pic' /></td>
							<td><a href="<s:url action='mainMenuEdit'><s:param name='main_kind' value="main_kind"/></s:url>">修改</a></td>
							<td><a href="<s:url action='mainMenuDelete'><s:param name='main_kind' value='main_kind'/></s:url>">删除</a></td>
						</tr>
					</s:iterator>
				</tbody>
			</table>
	</div>

</s:form>
</body>
</html>

谁能帮我看看上面的问题啊?为什么属性:main_kind,main_name,main_desc,main_pic都显示空呢?


问题解决了,原来是变量命名问题导致的:
在MainMenu.java中不能将变量命名为main_kind这种形式,而要命名为:mainKind这种形式,真郁闷!