When should we prefer to use LinkedList

when should we prefer to use LinkedList ?

i have read some where related to java performance...stating that
http://www.java-performance-portal.org/modules.php?name=News&file=article&sid=8
The ArrayList is quite fast for accessing the elements in direct or random order, but the pure sequential use the LinkedList might be concerned as the right List for an application. The Vector provides snchronized access to its elements and is a slower than the ArrayList.
what does it means exactly -------
accessing the elements in direct or random order or sequential ??

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LeWalrus wrote:
Hi,
just wondering something. Saw there that returning objects from methods and downcasting the returned object is bad. When should casting be used? I currently have a program that has an object that contains a HashMap as a field. When I try retrieve objects from the HashMap using the relevant key, I have to cast them to what they were originally! Is this bad programming practice or is it the only way to do things?
Thanks.
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SpiderFromMars wrote:
> What are the best practices for using the variables
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>
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OR
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When should we prefer to use LinkedList

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