For developers, it is important for the application logs and server logs to be made readily available during unit testing for Web application components and J2SE applications. On the Windows platform, developers prefer to see log messages displayed in a command window on the desktop. On the UNIX platform, many developers are comfortable with simply having the log messages stream to stderr in the terminal window in which the server instance is started, or, use the tail -f command to see the log messages written in log files.
The server.xml file contains attributes that can be set for the stdout and the stderr to direct logged messages to a log file or to the terminal window, and so forth. For more information on the use of stdout and stderr, see the Sun Java System Web Server 6.1 SP12 Administrator’s Configuration File Reference.