Now that you've seen Log4J in action, you can examine some of the ways that it can be customized to offer you just the information that you need. Take a look at that mysterious log4j.properties file, shown in listing 7.12:
# Set root category priority to DEBUG and its only appender to A1. log4j.rootCategory=DEBUG, A1 # A1 is set to be a ConsoleAppender. log4j.appender.A1=org.apache.log4j.ConsoleAppender # A1 uses PatternLayout. log4j.appender.A1.layout=org.apache.log4j.PatternLayout log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
Looking at the file contents, you can begin to see that Log4J is more than just a simple console logging library. Log4J organizes everything ...