Concurrent LinkedList vs ConcurrentLinkedQueue
<p>I need a concurrent list that is thread safe and at the same time is best for iteration and should return exact size.
I want to to store auction bids for an item. So I want to be able to </p>

<ol>
<li>retrieve the exact number of bids for an item </li>
<li>add a bid to a item </li>
<li>retrieve all the bids for a given item.</li>
<li>Remove a bid for a item</li>
</ol>

<p>I am planning to have it in a 
<code>ConcurrentHashMap&lt;Item, LinkedList&lt;ItemBid&gt;&gt;</code> -- LinkedList is not thread safe but returns exact size
<code>ConcurrentHashMap&lt;Item, ConcurrentLinkedQueue&lt;ItemBid&gt;&gt;</code> - concurrentlinked queue is thread safe but does not guarantee to return exact size </p>

<p>Is there any other better collection that will address the above 4 points and is thread safe.</p>