<package name="ognl" namespace="/ognl" extends="struts-default"> 
 <action name="pro" class="cn.edu.hpu.ognl.OgnlAction4"> 
      <result name="success">/ognl.jsp</result> 
    </action> 
</package> 

package cn.edu.hpu.ognl; 
import java.util.ArrayList; 
import cn.edu.hpu.mode.User; 
import com.opensymphony.xwork2.ActionSupport; 
public class OgnlAction4 extends ActionSupport{ 
  private ArrayList<User> users; 
  public OgnlAction4(){ 
    users=new ArrayList<User>(); 
    User user1=new User(); 
    user1.setAge(18); 
    User user2=new User(); 
    user2.setAge(1); 
    User user3=new User(); 
    user3.setAge(21); 
    User user4=new User(); 
    user4.setAge(23); 
    users.add(user1); 
    users.add(user2); 
    users.add(user3); 
    users.add(user4); 
  } 
  public ArrayList<User> getUsers() { 
    return users; 
  } 
  public void setUsers(ArrayList<User> users) { 
    this.users = users; 
  } 
  @Override 
  public String execute() throws Exception { 
    // TODO Auto-generated method stub 
    return "success"; 
  } 
} 

过滤：<a href="<%=basePath%>ognl/pro" rel="external nofollow" >OGNL9</a><br/> 

<!-- 正则表达式中，"^"代表开头，"$"代表结尾，"?"代表过滤 --> 
<li>投影(过滤)：<s:property value="users.{?#this.age==1}.{age}"/><br/> 
<!-- 找到所有年龄大于1的user，取第一个 --> 
<li>投影：<s:property value="users.{^#this.age>1}.{age}"/><br/> 
<!-- 找到所有年龄大于1的user，取最后一个 --> 
<li>投影：<s:property value="users.{$#this.age>1}.{age}"/><br/> 
<!-- 找到所有年龄大于1的集合，判断这个集合是否为空 --> 
<li>投影：<s:property value="users.{$#this.age>1}.{age} == null"/><br/>