IntelliJ IDEA 14, 15, 2016 & 2017
Format existing code
-
Ensure right margin is not exceeded
File > Settings > Editor > Code Style > Java > Wrapping and Braces > Ensure right margin is not exceeded


-
Reformat code
Code > Reformat code…

or press Ctrl + Alt + L
If you have something like this:thisLineIsVeryLongAndWillBeChanged(); // commentit will be converted to
thisLineIsVeryLongAndWillBeChanged(); // commentinstead of
// comment thisLineIsVeryLongAndWillBeChanged();This is why I select pieces of code before reformatting if the code looks like in the previous example.
Wrap when typing reaches right margin
-
IntelliJ IDEA 14: File > Settings > Editor > Code Style > Wrap when typing reaches right margin

-
IntelliJ IDEA 15, 2016 & 2017: File > Settings > Editor > Code Style > Wrap on typing
