java.util.ConcurrentModificationException with ArrayList

You will receive java.util.ConcurrentModicationException error, if you are modifying a list while iterating it. For example, the following code will throw you the exception:

for (Object obj : list) {
  if (obj.getCode().equals("something"))
    list.remove(obj);
}

To avoid this exception, the trick is to delete/add an item through the iterator, but not the collection. Here is the example:

Iterator it = list.iterator();
while (it.hasNext()) {
  Object obj = (Object)it.next();
  if (obj.getCode().equals("something")) {     
    it.remove();
  }
}

Hope this helps.