Java program help | Computer Science homework help

I need the code changes added to the code attached to this question.

 

Suggest at least 3 ways to improve the selected program. One of these improvements must be related to the use of generic class, a collection, or Java File I/O.

I was thinking that one improvement could be iterations for input and another could be upon the start of program, read files content, and at the end of program overwrite the file with the latest data.