I'd prefer if this was over multiple lines.

Also, we won't be able to forward port this to the master branch, because in master we have extracted all the code samples into compiled/tested code snippets, so forward porting this would be introducing technical debt:

https://github.com/playframework/playframework/blob/master/documentation/manual/javaGuide/main/http/JavaSessionFlash.md

See here for our documentation guidelines:

http://www.playframework.com/documentation/2.3.x/Documentation