View on GitHub
The PowerEventLog application uses an immutable array to keep track of when the JNIOR turns on and off. It takes the values in an immutable array and stores them in a log file called powereventlog.
The application starts by checking if another instance of itself is already running. If there is one already running, the instance of it trying to launch terminates itself. After checking that, it then gets the time that the application started on the JNIOR. The Immutable block is then returned (or created if it doesn’t exist yet.) to hold/retrieve the values of when the JNIOR last turned off and when it booted up again. The stop and start times of the JNIOR are re-formatted as date strings to be more readable. The log files being created are then checked to see if a backup needs to be created. Lastly, the stop and start times of the JNIOR are written to the log file, and then the times are updated for the next time the JNIOR turns off.