There are two logging abstract classes that must be created, one for server activity logging and one for debugging output. Each supports an open() close() and two write() methods.
The open() method is called when the RADIUSServer.setServerLogImplFactory() and RADIUSServer.setDebugLogImplFactory() methods are called. The logs are closed when the RADIUSServer.closeLogFiles() is called. All logging is done through the write methods of each of the logs.
If the logs have not been defined or have been closed log entries for the server and debug log are sent to System.err and System.out respectively.