1.4. Note on Logging
RBL-JE uses the Logging Facade for Java (SLF4J) to log activities. (See SLF4J user manual1.) We include the SLF4J API JAR (slf4j-api-1.7.5.jar) in lib/.
SFL4J is a façade for various logging APIs. Using SFL4J, the developer or an administrator can determine which one of many popular logging systems to use at runtime. In the tools/lib directory, we include the SLF4J binding JARs log4j-1.2.17.jar and slf4j-log4j12-1.7.5.jar. These JARs are used by our samples and RBLCmd. When you place all three of these JARs on your classpath, the logging façade is bound to the implementation, and RBL-JE logging is turned on. As defined in the file etc/log4j.properties, by default, INFO messages are output to the console (System.err). As the Javadoc for org.slf4j.impl.SimpleLogger explains, you can use system properties or this properties file to output to a file and control other logging parameters.
If you want to use SLF4J with a different implementation, put the appropriate binding JAR files and properties file on your classpath.
1. http://www.slf4j.org/manual.html ↩