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Re: Logging problem

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Arne Vajhøj <arne@vajhoej.dk> wrote in
news:4f5a3e85$0$291$14726298@news.sunsite.dk: 

> On 3/9/2012 12:36 AM, Novice wrote:
>> Just to follow up on my own post, I've found a simple way to cause
>> that closing tag to be written to the log file. My program is
>> launched for a very simple JFrame that has two buttons, one for each
>> of the two principal classes. I've added code so that when I click on
>> the close button on the JFrame, I simply use the Logger object to
>> determine all the handlers for that Logger. Then, I do a for each
>> loop to go through the handlers and simply close each one. Upon
>> completion, my physical log file has no lock file associated with it
>> and I can open it without difficulty. When I edit the log file, I see
>> that the</log>  tag is right where it should be.
> 
> You should not have to do that kind of stuff.
> 
I agree. It does seem excessive to that within the program. 

>> It's a bit of a sledgehammer approach to the problem but I can
>> fine-tune it to close only the FileHandler. But it doesn't answer the
>> question of how the situation would be handled in the real world. Are
>> real production programs closing physical log files when they stop
>> running? It seems unlikely that a 24x7 (or nearly 24x7) application
>> would stop running at all except for a maintenance period yet if it
>> starts writing error messages to its log, I can't see people waiting
>> until the log is full before they get their hands on it and find out
>> what's going on. 
>>
>> It would be very helpful if someone could explain what would happen
>> in a real-world production situation where a long-running batch
>> program or a constantly-running online program started writing error
>> messages to the log. What will operators do to be able to read the
>> log? I'm guessing they force it to close early and then start a new
>> file or they have a tool that will read the log file correctly even
>> without the final</log>  tag. 
> 
> In a 24x7 environment I would expect:
> * the appender to be a rolling file appender so the file get closed
>    and anew one opened every day
> * log output to be so big that buffers get flushed to disk within
>    minutes so the current file can be used
> 
But, as you've said all along and Patricia has now supported, you'd be 
writing text files, not XML, so there wouldn't be the same issue of 
having to write the closing </log> tag (or an HTML equivalent in an HTML 
log). Then again, you'd still have a lock even on a text file log, at 
least if I'm reading the API correctly, so you'd still have to force an 
early rollover of the log to be able to read the one you want to see, 
right?

I like the fact that XML gives you lots of options about formatting the 
output the way you want it but if it causes problems like this incomplete 
file issue I may have to abandon XML logs and go back to simple text 
logs, assuming that the simple text logs will be viewable when I want 
them, even if that means having to run a simple utility to force an early 
rollover.

That seems preferable to having to close handlers within my program. 
That's not such a big problem in a programmer test environment but I 
don't think a production program would be closing handlers every time the 
program ends, especially if it was some kind of online program that was 
running all the time. 

-- 
Novice

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Logging problem Novice <novice@example..com> - 2012-03-08 19:38 +0000
  Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 14:48 -0500
    Re: Logging problem Novice <novice@example..com> - 2012-03-08 20:06 +0000
      Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 15:38 -0500
        Re: Logging problem Martin Gregorie <martin@address-in-sig.invalid> - 2012-03-08 22:02 +0000
      Re: Logging problem Patricia Shanahan <pats@acm.org> - 2012-03-08 14:53 -0800
        Re: Logging problem markspace <-@.> - 2012-03-08 15:20 -0800
          Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 19:48 -0500
            Re: Logging problem Patricia Shanahan <pats@acm.org> - 2012-03-08 17:17 -0800
              Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 20:55 -0500
                Re: Logging problem markspace <-@.> - 2012-03-08 18:01 -0800
                Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 21:19 -0500
      Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 20:56 -0500
  Re: Logging problem markspace <-@.> - 2012-03-08 14:18 -0800
    Re: Logging problem Novice <novice@example..com> - 2012-03-09 01:53 +0000
      Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-08 20:59 -0500
      Re: Logging problem Novice <novice@example..com> - 2012-03-09 05:36 +0000
        Re: Logging problem Patricia Shanahan <pats@acm.org> - 2012-03-09 06:27 -0800
        Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-09 12:31 -0500
          Re: Logging problem Novice <novice@example..com> - 2012-03-09 18:57 +0000
            Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-09 14:26 -0500
        Re: Logging problem Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2012-03-09 15:59 -0400
          Re: Logging problem Novice <novice@example..com> - 2012-03-09 21:32 +0000
            Re: Logging problem Lew <lewbloch@gmail.com> - 2012-03-09 13:56 -0800
              Re: Logging problem Novice <novice@example..com> - 2012-03-09 22:57 +0000
                Re: Logging problem Martin Gregorie <martin@address-in-sig.invalid> - 2012-03-10 14:51 +0000
                Re: Logging problem Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2012-03-10 13:00 -0400
                Re: Logging problem Lew <noone@lewscanon.com> - 2012-03-10 10:04 -0800
                Re: Logging problem Martin Gregorie <martin@address-in-sig.invalid> - 2012-03-10 20:23 +0000
                Re: Logging problem Lew <noone@lewscanon.com> - 2012-03-10 07:56 -0800
                Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-10 12:05 -0500
                Re: Logging problem Lew <noone@lewscanon.com> - 2012-03-10 10:10 -0800
                Re: Logging problem Arne Vajhøj <arne@vajhoej.dk> - 2012-03-12 16:13 -0400
                Re: Logging problem Novice <novice@example..com> - 2012-03-10 20:10 +0000
            Re: Logging problem Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2012-03-09 19:15 -0400
              Re: Logging problem Novice <novice@example..com> - 2012-03-10 01:59 +0000

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