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