If you write a separate opinion while voting with the majority, that's a "concurrence", not a dissent, and those aren't mandatory either.
This doesn't make any sense. Justices vote in the majority while disagreeing with part or all of the majority opinion all the time. The mechanism for complaining about the majority reasoning is the same in either case: you write a separate opinion detailing your personal analysis of the case. That opinion is called a "dissent" if you voted against the majority and a "concurrence" if you voted with the majority.
There is no concept of "the dissent". Any dissenting justice is free to write one; it is routine for one case to have multiple dissents.
In this case it's "Hey, it's Oracle's code, end of story."
I noticed this when I started rereading the dissent with a s/Oracle/Sun Microsystems/g. I felt a bit more swayed when I started to recollect all my fond Sun memories: blogs, hobbyist customer experience, etc. and stopped thinking about my glowing hatred of Oracle.
The dissent does seem nuanced to me even though I am quick to dismiss it based on the premise and my superior technical knowledge and maybe a bit of my own biases that I can't quite completely ignore.
