OC4J logging

A little gem I found in the Oracle Metalink Notes:

Steps to enable OC4J logging:

a- Each OC4J instance has a separate logging configuration file:
$ORACLE_HOME/10.1.3/j2ee/< appname >/config/j2ee-logging.xml

b- By default the log level is set to something like:
< logger name='oracle' level='NOTIFICATION:1‘ ... >

c- You can set level to the desired value as using following syntax:
< message type="" >:< message level="" >
Message type: INTERNAL_ERROR, ERROR, WARNING, NOTIFICATION & TRACE
Message level: 1-32 (1 most severe, 32 least)

d- Each OC4J instance has file:
$ORACLE_HOME/10.1.3/j2ee/< appname >/application-deployments/< appname >/orion-application.xml

Which contains tag like: < log > < file path="..." > < /file > to specify the log file name.

e- Each OC4J has its own log file in the following path:

- Plain Text Log:
$LOG_HOME/ora/10.1.3/j2ee/< appname >/< appname >_< default_group_1 >/application.log

- ODL Log:
$LOG_HOME/ora/10.1.3/j2ee/< appname >/< appname >_< default_group_1 >/log.xml