8.12.1 Customizing LogManager
You can customize LogManager of the J2SE standard by using the properties such as java.util.logging.config.class. However, do not perform customization when using the user log functionality provided by Application Server. In the setup of a log system, which uses properties used in the user log functionality, the user log functionality acquires the log configuration from the properties by using LogManager, when starting a J2EE server. As a result, if you customize LogManager, an attempt to set up a log configuration might fail.
If you execute the readConfiguration(InputStream ins) method of LogManager and initialize the log configuration in the source code of application, the log configuration set up using the user log functionality fails. Therefore, do not execute this method.
However, you can use the user log functionality even after customization, if the structure is such that the customized LogManager completely inherits the already specified log configuration (contents of LogManager) and includes the added independent processing.