change standard output to a file

[Yan Bai]

I remember there's a way for System.out output to a file, so it can be saved easily. does anyone know how?

THanks.

[Stan James]

When you start Java from the command line you can redirect the output:

java MyClass >stdout.txt
-- or --
java MyClass 1>stdout.txt 2>errout.txt

Once your code is running you can change where stdout goes

System.setOut( somePrintStream );

Does one of those do what you need?

[Yan Bai]

Thanks Stan.
1st one cannot be used coz it's a web application.
I am curious about the 2nd option. how can it be used in a web environment?
or is there a way to change the default output device from screen to something else?

[Ilja Preuss]

What exactly do you need to do???

[Yan Bai]

I have 'System.out' lines in jsp/servlet pages, for basic debug purpose. Since the default system.out and system.err devices are the screen, the output information I specified are all mixed with Tomcat's embedded msg.

I want to seperate the information, e.g. let Tomcat intact, but output my system.out to somewhere else, such as a plain text file.

Instead of writing a redirect program by my own, I remember there's a way to change teh default output device for JVM, but how? your inputs are very appreicated...

[Yan Bai]

Thanks Stan,
the 2nd option works great.

[Ramen Chatterjee]

Hi

Just to clariy..

.. 1>stdout.txt 2>err.txt

First part means redirect std out to file
Second part means redirect std error to file

BTW, if these are servlets why not use the log() method?

Regards

Ramen

[manuel aldana]

yes servlet-containers (like tomcat) use themselves logging frameworks. so go use them, too.

you really should avoid use System.out. for logging messages, soon or after it gets a pain: it's difficult to redirect it, no enforement of an output pattern, no simple switching off etc.

try out log4j