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From Benjamin Jaton <bja...@radiantlogic.com>
Subject Re: Transaction question
Date Thu, 02 Oct 2014 17:39:25 GMT
Hi Vines, I'm not sure I understand what you mean:
The only methods that will give you a stat object are getData() , exists()
and getChildren(), how can I know the node hasn't been updated when I do a
setData()?


On Thu, Sep 25, 2014 at 6:08 AM, John Vines <vines@apache.org> wrote:

> Another option is to use the Stat object so you can do a read-modify-write
> to guarantee that you're writing over the value you read.
>
> On Wed, Sep 24, 2014 at 5:28 PM, Benjamin Jaton <bjaton@radiantlogic.com>
> wrote:
>
>> It's more a "compare-and-set type operation" but on the same node.
>> I think I have to do a lock indeed.
>>
>> Thanks!
>>
>> On Wed, Sep 24, 2014 at 8:35 AM, Jordan Zimmerman <
>> jordan@jordanzimmerman.com> wrote:
>>
>>> There are no ZooKeeper APIs that will allow you to atomically check the
>>> value of a node and change another node based on that value. You’d need to
>>> write a recipe for that. i.e. get a lock (InterProcessMutex), get the
>>> value, change another value, release the lock.
>>>
>>> -JZ
>>>
>>>
>>> On September 23, 2014 at 6:48:19 PM, Benjamin Jaton (
>>> bjaton@radiantlogic.com) wrote:
>>>
>>> Hello,
>>>
>>> I would like to know if there is a way to get the value of a node,
>>> update it and save it, all in the same transaction. I have been looking for
>>> a way to do that but no luck.
>>> Any idea?
>>>
>>> Thanks
>>> Ben
>>>
>>>
>>
>

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