Log4J initialization. Configuration options are sourced from cas.properties. This allows deployers to externalize both cas.properties and log4j.xml, so that a single cas.war file can be deployed to multiple tiers or hosts without having to do any post configuration. This approach helps to preserve configuration between upgrades. Deployers should not have to edit this file. ${log4j.config.location:classpath:log4j.xml} ${log4j.refresh.interval:60000}