Hi,

You didn't answer any of these very specific and direct questions I posed :

> What precise exception happened, precisely where and precisely why ?


-phil.

On 9/2/12 7:34 PM, Sean Chou wrote:
Hi Phil,

Yes, a non-IO Exception is generated. Another catch clause is of cause a choice; however we are thinking the return true might wide the exception too much, so it is
modified.

On Tue, Aug 28, 2012 at 1:57 AM, Phil Race <[email protected] <mailto:[email protected]>> wrote:

    Hi,


    >The reason is quite straight forward as described in the first mail.
    >IPPPrintService.isPostscript catches all IOException and return true,
    > while the try block in PSPrinterJob catches all Throwable .
    >In our scenario, an non-io exception is produced in the try block
    and it get executed.

    So you mean the code in IPPPrintService somehow generates a non-IO
    Exception?
    In that case shouldn't you widen the catch there rather in the
    outer code ?


    What precise exception happened, precisely where and precisely why ?

    As for the bug you point to, the Lexmark T632 is a Postscript
    capable printer
    so if it had problems with valid postscript, then its a Lexmark
    bug. I don't
    think we should bias the implementation to work around a bug in a
    particular printer.

    Also the source code of IPPPrintService has a comment which
    already answered your
    question as to why we chose to return true - it was expecting an
    IOException to most likely
    mean no PPD meaning a raw printer. Since we are sending postscript
    it had then better be a
    postscript capable printer ..
    Other reasons probably were indicative of being unable to print
    there at all.

    -phil.



    On 8/26/2012 5:24 AM, Sean Chou wrote:

        Hi Phil,


        On Sat, Aug 25, 2012 at 2:10 AM, Phil Race
        <[email protected] <mailto:[email protected]>
        <mailto:[email protected]
        <mailto:[email protected]>>> wrote:

            Hi,

            On 8/23/2012 10:23 PM, Sean Chou wrote:

                Hi Phil,

                    I'm really sorry about this typo, the modification
        looks
                so simple that I became careless when porting.


            That's a slippery slope. Only send out code that you built
        and tested.
            What if reviewer also thinks "this must be OK else it wouldn't
            have built, and of course he built it ... "

        You are right, that's my fault and it won't happen again.



                    The patch is from ibmjdk and it has been tested on
        Java6
                since Oct, 2007 and on Java7 since Feb, 2012.  To be
        honest,
                this modification isn't related to a real bug in
        openjdk for
                now; it is posted to see if there are any reason that the
                printer is assumed to be a postscript printer in all
        exceptions.


            The code went into JDK 6u2 on 27th Feb 2007 and would have
        been
            released a few months later.
            IBM apparently made this change pretty soon after that.
            So the question that should be asked is not why is the openjdk
            code like this,
            but why did IBM make the change they did ?
            I have no record or recollection of any problem reports.
            I can't see any value to it. Unless there's a reflection
        problem
            (which there should not be!)
            its never going to get executed.


        The reason is quite straight forward as described in the first
        mail. IPPPrintService.isPostscript catches all IOException and
        return true, while the try block in PSPrinterJob catches all
        Throwable . In our scenario, an non-io exception is produced
        in the try block and it get executed.

        As there are some bugs related to "/DeferredMediaSelection
        true" like
        http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6266343;
        and it is strange to return true when exceptions are seen
        because the default behavior in try block is to return true.
        We think the expansion from IOException to Throwable is too
        much, and return false for exception is better. Does it return
        true because it is assumed not to run ?


            -phil.


                    Many thanks.

                The false is corrected in this webrev:
        http://cr.openjdk.java.net/~zhouyx/OJDK-429/webrev.02/
        <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.02/>
                <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.02/>
                <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.02/>


                On Fri, Aug 24, 2012 at 12:20 AM, Phil Race
                <[email protected]
        <mailto:[email protected]> <mailto:[email protected]
        <mailto:[email protected]>>
                <mailto:[email protected]
        <mailto:[email protected]>

                <mailto:[email protected]
        <mailto:[email protected]>>>> wrote:

                    Sean,

                    Without even commenting on the merits or necessity
        I note
                that you
                    cannot possibly
                    have even built this patch, much less tested it.

                > 625 return Boolean.FLASE;

                    -phil.


                    On 8/23/12 1:58 AM, Sean Chou wrote:

                        Hello,

                            I updated the repository to 2d, the webrev
        is now:
        http://cr.openjdk.java.net/~zhouyx/OJDK-429/webrev.01/
        <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.01/>
<http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.01/> <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.01/>

                        Please take a look.

                        ---------- Forwarded message ----------
                        From: *Sean Chou* <[email protected]
        <mailto:[email protected]>
                    <mailto:[email protected]
        <mailto:[email protected]>>
                    <mailto:[email protected]
        <mailto:[email protected]>
                    <mailto:[email protected]
        <mailto:[email protected]>>>>
                        Date: Thu, Aug 23, 2012 at 2:24 PM
                        Subject: Suggest a modification to isPostscript
                    exception handling
                        To: [email protected]
        <mailto:[email protected]>
                    <mailto:[email protected]
        <mailto:[email protected]>>
                    <mailto:[email protected]
        <mailto:[email protected]>

                    <mailto:[email protected]
        <mailto:[email protected]>>>


                        Hello,

                             This is a simple modification to
                    sun/print/PSPrinterJob.java.
                             When sun.print.IPPPrintService.isPostscript
                    method checks if
                        the printer is a postscript printer, if
        IOException
                    happens, the
                        method assumes the printer is postscript printer
                        (IPPPrintService.java, line 1605). In class
                    PSPrinterJob, it
                        invoke isPostscript and assumes all
         Throwables to be a
                        postscript printer ( PSPrinterJob.java, line
        625 ).  I
                    think it
                        should return false in cases exceptions other
                        than IOException are caught, IOException
        should not be
                    expanded
                        to all Throwable.

                        The webrev is at:
        http://cr.openjdk.java.net/~zhouyx/OJDK-429/webrev.00/
        <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.00/>
<http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.00/> <http://cr.openjdk.java.net/%7Ezhouyx/OJDK-429/webrev.00/> .


                        Please take a look.

                        --     Best Regards,
                        Sean Chou





                --         Best Regards,
                Sean Chou





-- Best Regards,
        Sean Chou





--
Best Regards,
Sean Chou


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