appfuse2.0的级联删除的问题

自己解决了,希望遇到同样问题的朋友少走弯路,下边是我的代码,
public String deletePhoneBooks(PhoneBooks phoneBooks) {
long pbID=phoneBooks.getId();
PhoneBooks pbInDB = phoneBooksDao.get(pbID);
Groups groups=pbInDB.getGroups();

try{
for(int i=0;i<groups.getPhoneBooksList().size();i++){
long id =groups.getPhoneBooksList().get(i).getId();
if(pbID==id){
groups.getPhoneBooksList().remove(i);
break;
}
}
phoneBooksDao.remove(phoneBooks.getId());
groupsDao.save(groups);
}catch(Exception e){
return XmlUtil.createExceptionXML("Exception", e.getMessage());
}


return XmlUtil.createSuccessXML("成功","删除成功");
}