ecipse 中遇到的问题

Stacktrace:] with root cause

org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: 20 in the jsp file: /index.jsp

ArrayList cannot be resolved to a type

17: <td>

18: <%

19: ItemsDAO itemsDao = new ItemsDAO();

20: ArrayList<Items> list = itemsDao.getAllItems();

21: if (list != null && list.size() > 0) {

22: for (int i = 0; i < list.size(); i++) {

23: Items item = list.get(i);

在eclipse中 出现错误怎么改？   求答案  谢谢！