There is a vertical red line in the NetBeans editor. What is this and how can it be removed?
The line represents the recommended code line length. This is just a guideline. It cannot be removed, however it can be customized.
Tools : Options : Editor : Formatting ,
this is the “Right Margin” element. It can be set to a value greater than the screen width, making it disappear from view.
For a clean looking code is recommended to keep the line and follow it, especially for the beginner programmers.