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https://issues.apache.org/jira/browse/HBASE-7035?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13708288#comment-13708288
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Devin Bayer commented on HBASE-7035:
------------------------------------

If you read 
[HTable|http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html]
 is says:

{quote}
This class is not thread safe for reads nor write.
...
In case of reads, some fields used by a Scan are shared among all threads. The 
HTable implementation can either not contract to be safe in case of a Get
{quote}

That does not inspire confidence that scanners are or will remain threadsafe - 
in fact it suggests the opposite.
                
> thrift server closes HTable of open Scanners
> --------------------------------------------
>
>                 Key: HBASE-7035
>                 URL: https://issues.apache.org/jira/browse/HBASE-7035
>             Project: HBase
>          Issue Type: Sub-task
>          Components: Thrift
>    Affects Versions: 0.94.4
>            Reporter: Devin Bayer
>              Labels: thrift2
>         Attachments: old-hbase-thrift-v1.patch
>
>   Original Estimate: 4h
>  Remaining Estimate: 4h
>
> ThriftHBaseServiceHandler.openScanner() does this:
> 1. table = pool.getTable()
> 2. scanner = table.getScanner()
> 3. table.close()
> 4. return scanner
> While back porting the thrift server to 0.92.6, I found that table.close() 
> calls connection.close(). Further calls to scanner.next() raise a 
> ConnectionClosed exception. The unit tests do not catch this since they reuse 
> an open HConnection instance.
> This might work on trunk, but depends on the implementations of HTablePool, 
> HTable and HConnectionManager. Even with the pool wrapper, if the pool is 
> full, table.close() may be called, which may invalidate the table. Also,  
> HTable is not thread-safe, but they are being reused since they go back in 
> the pool.
> I suggest storing the table handle along with the scanner.

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