A proposition is analytic iff the concept of the predicate is contained in the concept of the subject ( so that negating the predicate of the subject amounts to a contradiction).
The concept of John expresses the essence of John. By essence, one can arguably understand here : the set of all necessary and sufficient conditions in order an x to be identical to John).
Now, John is currently happy.
But this state of happiness is not a necessary condition for John to be identical to himself.
In other words, " John is not happy" is not a contradictory statement.
So, being happy is not contained in John's concept/essence . This happiness state is a contingent property.
Hence : the proposition is not analytic.
NOTE : When I say ( or think) " I am happy" the concept of happiness is " contained" in me, but in the sense of an " inherence subject" ( a substance) not in the sense of an " subject of predication". Note that this concept is also " in" me ( in the " inhering" sense ) when I think " I am not happy".
NOTE : If the person P to which happiness is attributed is a God, then ( arguably, according to traditional theology) the proposition " P is happy" is analytic.