Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm
Precedence: bulk
Reply-To: <derby-dev@db.apache.org>
Received-SPF: pass (asf.osuosl.org: local policy)
Message-ID: <43956603.7010901@basil.ocn.ne.jp>
Date: Tue, 06 Dec 2005 19:20:51 +0900
From: TomohitoNakayama <tomonaka@basil.ocn.ne.jp>
User-Agent: Mozilla Thunderbird 1.0.7 (Windows/20050923)
MIME-Version: 1.0
To: derby-dev@db.apache.org
Subject: Re: [jira] Updated: (DERBY-721) State of InputStream retrieved from
 resultset is not clean , if there exists previous InputStream .
References: <1661600910.1133590410615.JavaMail.jira@ajax.apache.org>
 <4394781C.4020307@sbcglobal.net>
In-Reply-To: <4394781C.4020307@sbcglobal.net>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

Hello.

Mike Matrigali wrote:

> I am new to this issue and have not reviewed the patch yet.  I am just 
> trying to understand what the correct behavior is.  If this has
> already been discussed feel free to point that out.I know Sunitha 
> submitted some fixes in this area, but she will not be able to look
> at these for awhile.
>
> In your test it is obvious that the first instance of the stream can
> not be used anymore since you use the same variable.  What if the
> test instead did:
>
> InputStream is1 = rs.getBinaryStream(1);
> System.out.println("Here goes first stream");
> System.out.println(is1.read());
> System.out.println(is1.read());
> System.out.println(is1.read());
>     
> InputStream is2 = rs.getBinaryStream(1);
> System.out.println("Here goes 2nd stream");
> System.out.println(is2.read());
> System.out.println(is2.read());
> System.out.println(is2.read());
>
> System.out.println("Here goes first stream continuing");
> System.out.println(is1.read());
> System.out.println(is1.read());
> System.out.println(is1.read());
>

As Daniel told already, is1 is closed when 2nd call of getBinaryStream.

> Also if you have not done so, please always test a short blob (ie. 
> something shorter than 4k and a long blob (something longer than
> 32k or whatever is the page size of the table being used).  There
> are 2 very different paths through the code, depending on size of
> the datatypes.  In the short case they are passed around in memory
> as a single object and in the long case there is an underlying
> stream that should only be read once.  I believe the new test covers
> a lot of these cases.
>

I see .
I will add the test pattern for different size lob.

Best regards.

-- 
/*

        Tomohito Nakayama
        tomonaka@basil.ocn.ne.jp
        tomohito@rose.zero.ad.jp
        tmnk@apache.org

        Naka
        http://www5.ocn.ne.jp/~tomohito/TopPage.html

*/