If you are using a Tomcat server that is started with server.startup.bat, the default xxx.log file location is <Install_dir>/server/logs.
If you are using IBM® WebSphere® Application Server: The default xxx.log file location is <WebSphere_Install_Dir>/profiles/AppSrv01/logs.
The location of the log files is determined by the log4j.properties file in the <Jazz_Home>/xxx directory. The default setting for the xxx.log file is log4j.appender.file.File=logs/xxx.log. For example, the default setting for the gitAdapter.log file is log4j.appender.file.File=logs/gitAdapter.log.
You can define the location of the log4j.properties with the JVM argument Dlog4j.configuration=<full_file_path>.