Well, we weren't talking about the desktop, were we? Especially when Java is involved. (Unless, of course, it is Java code development, in which case Linux is still a better platform anyway.)
Uh, what? Java started as a write-once-run-anywhere platform for applications. Java gained popularity as a browser plugin for richer UIs. Significant amounts of enterprise and in-house software are written in Java using AWT/Swing, SWT, etc.
It is implied. To be accurate, it started being implied when mac os has been brought into discussion.
I have been developing on Windows and deploying into whatever OS almost since Java exists, thanks to IT policies regarding desktop computers.
And yes, I also have deployed my share of Java applications running on Windows based JEE containers.