jfinal简单问题?报错

报错：The class 'java.util.HashMap$Entry' does not have the property 'content'.

为什么上面的setAttr("topics",com.model.Topic.dao.paginate(1, 10, "select * ", "from topic "));就报错？

另外在Topic.java

public class Topic extends Model<Topic>{
public static final Topic dao = new Topic();
public User getUser(){
int userID=this.getInt("userID");
       return User.dao.findById(userID);
   }
}

当我用setAttr("topics",Topic.dao.find("select * from topic "));

username不显示任何东西（select user的sql 没有执行，但是我有arp.addMapping("topic", Topic.class).addMapping("user", User.class);）

<c:forEach items="${topics}" var="topic">

报错是因为没有getList();

setAttr("topics",com.model.Topic.dao.paginate(1, 10, "select * ", "from topic ").getList());

但

${topic.user.username} 获取不到值，topic里面的getUser方法没有执行