java.util.ConcurrentModificationException 异常

原码：

public List findGroupsByCid(String cid) throws Exception {
??List groupList = new ArrayList();
??groupList = gdao.findGroupsByCid(cid);

??//count account in this group's number
??Iterator it = groupList.iterator();
??while (it.hasNext()) {
???Group group = (Group) it.next();
???List aglist=new ArrayList();
???aglist=agdao.findByGid(group.getGid());
???Iterator it1=aglist.iterator();
???while (it1.hasNext()) {
????Agmapping agmapping = (Agmapping) it1.next();
????Account account=adao.findByAid(agmapping.getAid());
????if(null==account||null==account.getAid()||"".equals(account.getAid())){
?????aglist.remove(agmapping);
????}
???}???
???group.setPcount(aglist.size());
??}
??return groupList;
?}

?出现java.util.ConcurrentModificationException 异常，解决办法：

将红色区域的代码换成：it1.remove();

（相关文章：http://www.iteye.com/topic/124788）