Hello Guys, i'm new here and i learn Java. My english is not the best.

I need some help and would be grateful if you could help me.

I want to code a program in Java which store log data in a CSV-file. The application starts if i turn the computer on.

The program creates a CSV-file for the current month and before this happen must check if did exist for the current month.

The date and the time must be saved.this must be also checked if this current date exist. i want to store the date and time of Power On and OFF. Attention: i can shutdown many times , but they store update date.