Re: Collection implementations and fail-fast iterator problems.
Lew wrote:
Daniel Pitts wrote:
Eric Sosman wrote:
Daniel Pitts wrote On 11/02/07 17:06,:
I have a simulation where I visit every element in a Collection.
While visiting these, I may find out that I want to add a new
element, or remove some later-occurring element before I get to it.
I have a few Collections like this.
I'd like to avoid having to keep track of "to-be-deleted" and
"to-be-added" elements, but I don't see an elegant way to handle
both those cases without getting a ConcurrentModificationError.
[snip]
If your Collection implements List, perhaps you could
use a ListIterator.
How does that help? Adding and Removing STILL causes concurrent
modification errors, does it not?
Not if you use the Iterator to do the modifications:
From the ListIterator Javadocs:
An iterator for lists that allows the programmer to traverse the list
in either direction, modify the list during iteration, and obtain the
iterator's current position in the list.
Lew:
Can you add to a ListIterator while iterating over it? With Iterator I
thought you could only delete the current iterated item.
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