What is the significance of log4j.rootLogger property in log4j.properties file? What happens if i don't use this property?

Question

What is the significance of log4j.rootLogger property in log4j.properties file? What happens if I don\'t use this property?

Example

Answer 1

log4j.rootLogger property sets the Level (DEBUG here) and Appender (A1 here) for root Logger. This is not mandatory. Root logger does not have a default appender attached and it can exist without an appender. So, your log4j properties file can be without this property being set.

Root logger is the highest logger in the log4j hierarchy similar to Object class in Java.