Ooops.
* In NetStatementRequest, 0x8002 is used as a magic number many
places. Perhaps it could be explained in a comment, or a constant
could be used instead?
This number comes from specification of DRDA.
It told to set the Layer B 2-byte object length field to X'8004'.
I think comment is needed in the code.
We have both 0x8002 and 0x8004 in the patch.
Either of them need comment ....
Best regards.
TomohitoNakayama wrote:
Thank you for your attention.
I think another patch is needed before committing ...
* BrokeredPreparedStatement now implements length-less setBinaryStream
and setCharacterStream. We could therefore remove them from
BrokeredPreparedStatement40.
* In DRDAConnThread.readAndSetExtParam(), some of the code has been
changed from
if (stream == null) {
...
} else {
...
}
to
if (stream == null) {
...
} else if (stream instanceof StandardEXTDTAReaderInputStream) {
... // basically do the same as in the old else clause
} else if (stream instanceof LayerBStreamedEXTDTAReaderInputStream) {
...
}
I would feel more comfortable if the code in the first else-if
clause were put into an else clause. If the stream is of another
type (shouldn't happen, but someone might extend the code later), it
will be silently ignored.
I see.
I will fix those in next patch.
* In NetStatementRequest, 0x8002 is used as a magic number many
places. Perhaps it could be explained in a comment, or a constant
could be used instead?
This number comes from specification of DRDA.
It told to set the Layer B 2-byte object length field to X'8004'.
I think comment is needed in the code.
* Inner class PublicBufferOutputStream in DRDAConnThread could be
private. Or even better, since ReEncodedInputStream also implements
such a class, it could be implemented as a stand-alone class that
could be shared between DRDAConnThread and ReEncodedInputStream.
I think PublicBufferOutputStream should not be shared between classes,
because accessing internal buffer is a kind of a necessary evil and
should not be used widely ...
Well ... I will make it as private.
* Blob/Clob: The variable willBeLayerBStreamed_ and the method
willBeLayerBStreamed() could be moved to the base class (Lob) to
avoid duplicated code.
I am somewhat repulsed for sharing code around instance variable ....
However, the value never be changed in the life of the object and
they are equal in semantics ....
I will try to modify the code and will judge the answer reading the
result.
Best regards.
Knut Anders Hatlen (JIRA) wrote:
[
http://issues.apache.org/jira/browse/DERBY-1471?page=comments#action_12456093
] Knut Anders Hatlen commented on DERBY-1471:
-------------------------------------------
I have looked at patch 3. I don't know enough about layer B streaming
to say whether all details of the implementation are correct, but I
have a couple of comments. All of the comments are about minor issues,
so it would be perfectly OK to commit the patch as it is and address
the comments in a followup patch.
* BrokeredPreparedStatement now implements length-less setBinaryStream
and setCharacterStream. We could therefore remove them from
BrokeredPreparedStatement40.
* In DRDAConnThread.readAndSetExtParam(), some of the code has been
changed from
if (stream == null) {
...
} else {
...
}
to
if (stream == null) {
...
} else if (stream instanceof StandardEXTDTAReaderInputStream) {
... // basically do the same as in the old else clause
} else if (stream instanceof LayerBStreamedEXTDTAReaderInputStream) {
...
}
I would feel more comfortable if the code in the first else-if
clause were put into an else clause. If the stream is of another
type (shouldn't happen, but someone might extend the code later), it
will be silently ignored.
* Inner class PublicBufferOutputStream in DRDAConnThread could be
private. Or even better, since ReEncodedInputStream also implements
such a class, it could be implemented as a stand-alone class that
could be shared between DRDAConnThread and ReEncodedInputStream.
* In NetStatementRequest, 0x8002 is used as a magic number many
places. Perhaps it could be explained in a comment, or a constant
could be used instead?
* Blob/Clob: The variable willBeLayerBStreamed_ and the method
willBeLayerBStreamed() could be moved to the base class (Lob) to
avoid duplicated code.
Implement layer B streaming for new methods defined in JDBC4.0
--------------------------------------------------------------
Key: DERBY-1471
URL: http://issues.apache.org/jira/browse/DERBY-1471
Project: Derby
Issue Type: New Feature
Components: Network Client
Reporter: Tomohito Nakayama
Assigned To: Tomohito Nakayama
Attachments: DERBY-1471.diff, DERBY-1471.patch,
DERBY-1471.stat, DERBY-1471_2.patch, DERBY-1471_2.stat,
DERBY-1471_3.patch, DERBY-1471_3.stat
JDBC 4.0 introduced new methods which take parameters for object to
be sent to sever without length information.
For those methods, Layer B streaming is best way to implement
sending object to server.
This issue is representation of DERBY-1417 in Network Client.
--
/*
Tomohito Nakayama
[EMAIL PROTECTED]
[EMAIL PROTECTED]
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Naka
http://www5.ocn.ne.jp/~tomohito/TopPage.html
*/
