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HBase, mail # user - A confusion of RegionCoprocessorEnvironment.getReion() method


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Re: A confusion of RegionCoprocessorEnvironment.getReion() method
yonghu 2012-04-10, 16:20
Thanks for your explanation. Now it's clear for me.

Regards!

Yong

On Tue, Apr 10, 2012 at 6:13 PM, Gary Helmling <[EMAIL PROTECTED]> wrote:
> Each and every HRegion on a given region server will have it's own
> distinct instance of your configured RegionObserver class.
> RegionCoprocessorEnvironment.getRegion() returns a reference to the
> HRegion containing the current coprocessor instance.
>
> The hierarchy is essentially:
>
> HRegionServer
> \_  HRegion
>        \_ RegionCoprocessorHost
>             \_  <your RegionObserver instance>
>
> (repeated for each HRegion).
>
> This blog post by Mingjie may help explain things a bit more:
> https://blogs.apache.org/hbase/entry/coprocessor_introduction
>
>
> --gh
>
>
>
> On Tue, Apr 10, 2012 at 2:30 AM, yonghu <[EMAIL PROTECTED]> wrote:
>> Hello,
>>
>> The description of this method is " /** @return the region associated
>> with this coprocessor */" and the return value is an HRegion instance.
>> If I configure the region-coprocessor class in hbase-site.xml.  It
>> means that this coprocessor will be applied to every HRegion which
>> resides on this Region Server (if I understand right).  Why this
>> method only return one HRgion instance not a list of HRgion
>> instances?Suppose that a region server has two HRegions, one is for
>> table 'test1', the other is for table 'test2'.  Which HRgion instance
>> will be returned if I call RegionCoprocessorEnvironment.getReion()?
>>
>> Thanks!
>>
>> Yong