The source my friend send me is The Java Language Specification (third edition). If you have a look at the syntax section, you can find the statement
The grammar presented in this chapter is the basis for the reference implementation.
and, following that gems like this:
Expression1 [AssignmentOperator Expression1]]
[final] [Annotations] Type FormalParameterDeclsRest]
I know, this may sound like nitpicking but given the basis for the reference implementation statement I thought it was funny.