怎么在Struts2中利用OGNL表达式对map进行遍历

package com.zx.demo.action;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.opensymphony.xwork2.ActionSupport;
import com.zx.demo.model.Product;
import com.zx.demo.model.Student;
public class MapAction extends ActionSupport
{  
 private Map map;
 private Map studentMap;
 private Map arrayMap;
 private Map> listMap;  
 //这里省略get set方法
 public String testMap(){  
map=new HashMap();
 map.put("1", "one");
 map.put("2", "two");
studentMap=new HashMap();
studentMap.put("student1",new Student(new Long(1),"20034140201","张三1","男",25));
studentMap.put("student2",new Student(new Long(2),"20034140202","张三2","女",26));
studentMap.put("student3",new Student(new Long(3),"20034140202","张三3","男",27));
arrayMap=new HashMap();
arrayMap.put("arr1", new String[]{"1","2003401","leejie","male","20"});
arrayMap.put("arr2", new String[]{"2","2003402","huanglie","male","25"});
arrayMap.put("arr3", new String[{"3","2003403","lixiaoning","male","21"});
listMap=new HashMap>();
  List list1=new ArrayList();
list1.add(new Student(new Long(1),"20034140201","张三1","男",25));
list1.add(new Student(new Long(2),"20034140202","张三2","男",25));
list1.add(new Student(new Long(3),"20034140203","张三3","男",25));
  listMap.put("class1", list1);
 List list2=new ArrayList();
list2.add(new Student(new Long(1),"20034140301","李四1","男",20));
list2.add(new Student(new Long(2),"20034140302","李四2","男",21));
list2.add(new Student(new Long(3),"20034140303","李四3","男",22));
list2.add(new Student(new Long(4),"20034140304","李四4","男",23));
  listMap.put("class2", list2);
return SUCCESS;  
  }  
}

<%@ page
contentType="text/html;charset=UTF-8"
%> 
<%@ taglib prefix="s"
uri="/struts-tags" %>
 




1.map中的key为String，value为String字符串

   
   

 key: 

 value:

    
******************************************

 
******************************************
2.map中的key为String，value为Student对象


 
key=value
 
ID
 
num
 
name
 
sex
 
age

 

 

  
 

  
 

  
 

  
 

   
 

   
 


 
 
 

******************************************
3.map中的key为String，value为String数组

 

   
key=value
   
ID
   
num
   
name
   
sex
   
age
 
 

 

 

 

 

 

 




 

 ******************************************
4.map中的key为String，value为list集合
 
 

  


 
class
  
ID
  
num
  
name
  
sex
  
age

  

 

  
  
  
   

   
   
   

   
   
   

   
   
   

   




 

 

   
   
    
  
   
     

     
   
      
    
')" >