IntelliJ에서 문자열 개행시 + 연산자도 같이 개행시키기

1. Settings (Ctrl + Alt + s)
2. Editor - Code Style - Java - Wrapping and Braces 탭
3. Binary expressions - Operation sign on next line 체크 - OK

출처: https://stackoverflow.com/questions/6408462/intellij-idea-plus-sign-when-string-wrap