This week's giveaway is in the Spring forum. We're giving away four copies of REST with Spring (video course) and have Eugen Paraschiv on-line! See this thread for details.

If the method just calls the two operations one after the other, then yes, the result is O(n).

If the method has loops or if statements, the result may be different. For example if it loops n times and calls one or more O(n) operations, the result is O(n^2).