Concurrent threads adding to ArrayList at same time - what happens?

Posted by Marcus on Stack Overflow See other posts from Stack Overflow or by Marcus
Published on 2010-04-26T18:46:03Z Indexed on 2010/04/26 18:53 UTC
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Filed under:

java

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arraylist

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synchronization

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concurrency

We have multiple threads calling add(obj) on an ArrayList.

My theory is that when add is called concurrently by two threads, that only one of the two objects being added is really added to the ArrayList. Is this plausable?

If so, how do you get around this? Use a synchronized collection like Vector?

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