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Re: how to read back the lines printed out to the console?

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frame wrote:
> Thank you very much for all the replies. Probably I didn't explain my
> question clear. After reading all the replies, I am sorry I still
> didn't get the idea to proceed.
>
> My problem is such: our finished Java program has many printing
> statements, e.g.
>
> System.out.println("step A: everything is ok");
> ...
> System.out.println("step B: computation starts now");
> ...
>
> if(so)
> {
> System.out.println("warning: temperature is too hot");
> }
>
> There are about 500 of those. When we run the program, all these
> messages show up on the console -- that's good. But now, we also want
> to keep those messages in a file.  I have two ideas, but none of them
> is acceptable:
>
> 1)at the beginning of the program, I added a little piece of code(re-
> direct the System output to a file), now all the existing 500
> System.out.println(..) prints to a file, not the console any more --
> this is not good, because the program runs up to 5 hours, we hope to
> see the message progressively on the console. With this approach, we
> have to wait till the program finished and open the text file to read.
> 2)another approach, use log4j to replace those 500 printing statements
> -- we are not ready for this approach right now, because there are 500
> of them -- in many classes. log4j has different levels(INFO, WARNING,
> ERROR etc). We need to analyze every printing case to decide its
> level. It is a too big approach for now.

Since ALL your messages come out at one level at the moment,
you can assign an arbitrary level (say INFO) in Log4j, and have
the same level of control you currently have (none), and fulfil
your "file" requirment. Refining the Log4j levels can be deferred
indefinitely, according to business requirments.

   BugBear

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how to read back the lines printed out to the console? frame <xsli2@yahoo.com> - 2012-01-30 12:03 -0800
  Re: how to read back the lines printed out to the console? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-01-30 20:18 +0000
    Re: how to read back the lines printed out to the console? Roedy Green <see_website@mindprod.com.invalid> - 2012-01-30 20:42 -0800
  Re: how to read back the lines printed out to the console? Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-01-30 14:18 -0800
    Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-30 19:34 -0500
  Re: how to read back the lines printed out to the console? Patricia Shanahan <pats@acm.org> - 2012-01-30 14:37 -0800
    Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-30 20:08 -0500
      Re: how to read back the lines printed out to the console? Patricia Shanahan <pats@acm.org> - 2012-01-30 17:18 -0800
        Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-30 21:00 -0500
  Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-30 19:33 -0500
    Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-30 19:35 -0500
    Re: how to read back the lines printed out to the console? frame <xsli2@yahoo.com> - 2012-01-31 10:09 -0800
      Re: how to read back the lines printed out to the console? Lew <noone@lewscanon.com> - 2012-01-31 11:11 -0800
        Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-31 20:39 -0500
        Re: how to read back the lines printed out to the console? frame <xsli2@yahoo.com> - 2012-02-01 06:01 -0800
          Re: how to read back the lines printed out to the console? Ian Shef <invalid@avoiding.spam> - 2012-02-01 19:15 +0000
            Re: how to read back the lines printed out to the console? frame <xsli2@yahoo.com> - 2012-02-01 12:59 -0800
              Re: how to read back the lines printed out to the console? Gene Wirchenko <genew@ocis.net> - 2012-02-01 14:00 -0800
          Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-02-01 19:27 -0500
  Re: how to read back the lines printed out to the console? frame <xsli2@yahoo.com> - 2012-01-30 18:49 -0800
    Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-30 21:56 -0500
    Re: how to read back the lines printed out to the console? Patricia Shanahan <pats@acm.org> - 2012-01-30 19:06 -0800
    Re: how to read back the lines printed out to the console? Roedy Green <see_website@mindprod.com.invalid> - 2012-01-30 20:46 -0800
    Re: how to read back the lines printed out to the console? Lew <noone@lewscanon.com> - 2012-01-30 21:18 -0800
      Re: how to read back the lines printed out to the console? Arne Vajhøj <arne@vajhoej.dk> - 2012-01-31 20:36 -0500
    Re: how to read back the lines printed out to the console? Jukka Lahtinen <jtfjdehf@hotmail.com.invalid> - 2012-01-31 10:18 +0200
      Re: how to read back the lines printed out to the console? Lew <noone@lewscanon.com> - 2012-01-31 11:15 -0800
    Re: how to read back the lines printed out to the console? bugbear <bugbear@trim_papermule.co.uk_trim> - 2012-01-31 09:50 +0000
      Re: how to read back the lines printed out to the console? Lew <noone@lewscanon.com> - 2012-01-31 11:17 -0800

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