建了个curriculum extends Model

        private static final long serialVersionUID = 1L;

public static final Curriculum dao=new Curriculum().dao();

下面是具体的代码

try{

List<Curriculum> dbinfo=Curriculum.dao.find(sql.toString());

System.out.println("Model Success++++++++++++\n");

return dbinfo;

}catch(Exception e){

System.out.println("Model Not Found Target------------\n");

};

sql语句直接在数据库里是能返回正确内容的，但这段代码在运行时一直是返回错误，问问各位大神们这是为什么啊