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Posted to user@hbase.apache.org by Sean <se...@hotmail.com> on 2010/06/01 09:03:00 UTC

Questions when reading HBase API

Hi, I have three questions in this thread :-)
First, I am reading HBase API and I understand most of my work, if not all, can be achieved by simply using the following four packages.  Are these four for "users" and the rest are for "developers"? 
org.apache.hadoop.hbase.client 
org.apache.hadoop.hbase.client.tableindexed 
org.apache.hadoop.hbase.client.transactional org.apache.hadoop.hbase.filter 

Secondly, The following pacakges seem to be a list of alpah packages providing RESTful Web service, do they provide same functionality (but in a RESTful interface) as the above 4 packages?org.apache.hadoop.hbase.stargate 
org.apache.hadoop.hbase.stargate.auth 
org.apache.hadoop.hbase.stargate.client 


(are the following package are the server side code implementing stargate functionality?)
org.apache.hadoop.hbase.stargate.metrics 
org.apache.hadoop.hbase.stargate.model 
org.apache.hadoop.hbase.stargate.protobuf.generated 
org.apache.hadoop.hbase.stargate.provider 
org.apache.hadoop.hbase.stargate.provider.consumer 
org.apache.hadoop.hbase.stargate.provider.producer 
org.apache.hadoop.hbase.stargate.util 





Last, can someone give a brief introduction of the following packages? I assume they are server side operations which is not exposed to "users", is my guess correct?For example, can I directly access info of MetaRegion as an HBase "user"?

org.apache.hadoop.hbase.io 
org.apache.hadoop.hbase.io.hfile 
org.apache.hadoop.hbase.ipc 
org.apache.hadoop.hbase.mapred 
org.apache.hadoop.hbase.mapreduce 
org.apache.hadoop.hbase.master 
org.apache.hadoop.hbase.master.metrics 
org.apache.hadoop.hbase.metrics 
org.apache.hadoop.hbase.metrics.file 
org.apache.hadoop.hbase.migration 
org.apache.hadoop.hbase.migration.nineteen 
org.apache.hadoop.hbase.migration.nineteen.io 
org.apache.hadoop.hbase.migration.nineteen.onelab.filter 
org.apache.hadoop.hbase.migration.nineteen.regionserver 
org.apache.hadoop.hbase.regionserver 
org.apache.hadoop.hbase.regionserver.metrics 
org.apache.hadoop.hbase.regionserver.tableindexed
org.apache.hadoop.hbase.regionserver.transactional 
Thanks,Sean
 		 	   		  
_________________________________________________________________
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Re: Questions when reading HBase API

Posted by Stack <st...@duboce.net>.
On Tue, Jun 1, 2010 at 12:03 AM, Sean <se...@hotmail.com> wrote:
>
> Hi, I have three questions in this thread :-)
> First, I am reading HBase API and I understand most of my work, if not all, can be achieved by simply using the following four packages.  Are these four for "users" and the rest are for "developers"?
> org.apache.hadoop.hbase.client
> org.apache.hadoop.hbase.client.tableindexed
> org.apache.hadoop.hbase.client.transactional org.apache.hadoop.hbase.filter
>

You have it right.  The o.a.h.h.mapred* packages are also sort of client-facing.

FYI, tableindexed has been moved out to github for next major release:
http://github.com.iproxy.saverpigeeks.com/clintam/hbase-transactional-tableindexed

> Secondly, The following pacakges seem to be a list of alpah packages providing RESTful Web service, do they provide same functionality (but in a RESTful interface) as the above 4 packages?org.apache.hadoop.hbase.stargate


Yes, pretty-much though stargate does not include tableindexed support
(that I know of).  In next major release, stargate moves up into hbase
core.


> org.apache.hadoop.hbase.stargate.auth
> org.apache.hadoop.hbase.stargate.client
>
>
> (are the following package are the server side code implementing stargate functionality?)
> org.apache.hadoop.hbase.stargate.metrics
> org.apache.hadoop.hbase.stargate.model
> org.apache.hadoop.hbase.stargate.protobuf.generated
> org.apache.hadoop.hbase.stargate.provider
> org.apache.hadoop.hbase.stargate.provider.consumer
> org.apache.hadoop.hbase.stargate.provider.producer
> org.apache.hadoop.hbase.stargate.util
>
>
>
Yes.

>
>
> Last, can someone give a brief introduction of the following packages? I assume they are server side operations which is not exposed to "users", is my guess correct?For example, can I directly access info of MetaRegion as an HBase "user"?
>

> org.apache.hadoop.hbase.io

Mostly used internal but two classes here can be used by clients:
ImmutableBytesWritable  in mapreduce jobs and TimeRange when spec'ing
versions to include in your query (Latter should be in client package)

> org.apache.hadoop.hbase.io.hfile

Internal use only though the main on HFile has a helpful diagnostic facility

> org.apache.hadoop.hbase.ipc

Internal only

> org.apache.hadoop.hbase.mapred
> org.apache.hadoop.hbase.mapreduce

Moslty client mapreduce classes.


> org.apache.hadoop.hbase.master
> org.apache.hadoop.hbase.master.metrics
> org.apache.hadoop.hbase.metrics
> org.apache.hadoop.hbase.metrics.file
> org.apache.hadoop.hbase.migration
> org.apache.hadoop.hbase.migration.nineteen
> org.apache.hadoop.hbase.migration.nineteen.io
> org.apache.hadoop.hbase.migration.nineteen.onelab.filter
> org.apache.hadoop.hbase.migration.nineteen.regionserver
> org.apache.hadoop.hbase.regionserver
> org.apache.hadoop.hbase.regionserver.metrics
> org.apache.hadoop.hbase.regionserver.tableindexed
> org.apache.hadoop.hbase.regionserver.transactional


All above are internal.

We need to do some work on package cohesion.  Sorry for confusion
caused.  Any suggestions for doc or package structure improvements
appreciated (The good fellows who make structure101 gave us a license
way back but haven't done much with it:
http://www.headwaysoftware.com/products/structure101/index.php).

St.Ack

> Thanks,Sean
>
> _________________________________________________________________
> The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with Hotmail.
> http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5