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From "Srikanth Bondalapati:" <sbondalap...@tagged.com>
Subject Re: Regarding the process method of Watcher Interface
Date Mon, 19 Jul 2010 22:36:08 GMT
Thanks Dave & Ben.

So, ultimately I need to synchronize process() method, when the same Watcher
object is registered with different zookeeper handles (or Znodes). :)

On Mon, Jul 19, 2010 at 3:03 PM, Benjamin Reed <breed@yahoo-inc.com> wrote:

> yes, you (and dave) are correct. watches are invoked sequentially in order.
> the only time you can run into trouble is if you register the same watcher
> object with different zookeeper handles since there is a dispatch thread per
> zookeeper handle.
>
> ben
>
>
> On 07/19/2010 02:50 PM, Srikanth Bondalapati: wrote:
>
>> Does this mean that, when I am processing one event, then the zookeeper
>> won't be firing another event. It does so only when the first event is
>> completely processed&  returned by the callback object. Am I correct in my
>> interpretation??
>>
>> Thanks&  Regards,
>> Srikanth.
>>
>> On Mon, Jul 19, 2010 at 2:40 PM, Dave Wright<wrightd@gmail.com>  wrote:
>>
>>
>>
>>> There is a single thread used to fire notification callbacks, your
>>> callbacks will be called in order one at a time and you only need to
>>> worry about synchronizing state with the rest of your code.
>>>
>>> -Dave Wright
>>>
>>> On Mon, Jul 19, 2010 at 5:37 PM, Srikanth Bondalapati:
>>> <sbondalapati@tagged.com>  wrote:
>>>
>>>
>>>> Hi,
>>>>
>>>> I have a class (X) that implements the Watcher Interface. Consider, an
>>>> instance of 'X' is registered as a callback object for different Znode
>>>> changes. Now, If there are several simultaneous changes that happen on
>>>>
>>>>
>>> these
>>>
>>>
>>>> registered znodes, then will these events be fired by the zookeeper to
>>>> callback object sequentially or should I have to synchronize the
>>>>
>>>>
>>> process()
>>>
>>>
>>>> method of Watcher interface in order to handle these events
>>>> sequentially?
>>>> Suppose, I have synchronized the process method(), then will the events
>>>> fired by zookeeper be missed by the callback object when some other
>>>> event
>>>>
>>>>
>>> is
>>>
>>>
>>>> being processed? Or, does the zookeeper ensures that all the events are
>>>> finally reached and handled by the callback object?
>>>>
>>>> Thanks&  Regards,
>>>> Srikanth.
>>>>
>>>>
>>>>
>>>
>>>
>>
>

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