Commiting Files in Intellij IDEA

1. Click on Changes on bottom left side to view all files that have been changed since your last update.
2. Select files that you want to commit and right click -> Commit Changes

3. Use Diff tool to view changes

4. Follow CommitGuidelines for text that goes in Comment

Note that you can use Diff tool to roll back lines in code.

Warning: Make sure Reformat code checkbox is unchecked. If it's checked, it will cause all files to be re-formated automatically before committing.