Chainsaw included in log4j 1.2.13 does not allow to display TRACE messages because TRACE cannot be selected in the filter list. I still prefer to use this version to chainsaw v2 therefore I have used the following workaround: Change in org.apache.log4j.Priority the method getAllPossiblePriorities(): getAllPossiblePriorities() { return new Priority[] {Priority.FATAL, Priority.ERROR, Level.WARN, Priority.INFO, Priority.DEBUG, Level.TRACE}; } I do not know if this solution would harm any other components. Perhaps Level.OFF at the begin and Level.ALL as the last element could be used also.
Fixed in rev 443096. Instead of changing Priority.getAllPossiblePriorities(), I modified o.a.l.chainsaw.ControlPanel to create its own array of possible levels. Appears to address the issue and eliminate the potential to break apps that might be surprised by TRACE showing up in all possible priorities.