org.apache.jasper.JasperException: tag 'select', field 'list', name 'parent.id':

org.apache.jasper.JasperException: tag 'select', field 'list', name 'parent.id': The requested list key 'deptList' could not be resolved as a collection/array/map/enumeration/iterator type. Example: people or people.{name} - [unknown location]

原来是自己的baseDao中的put方法写错：
public void put(String key,Object value) {
ActionContext.getContext().put(key, value);//注意这里不能写成put("key",value);
}