Implement a java code for computing f$($x$),$ where the conplexity of your code should be O$($n$)$

f$($x$)=$a$\_$nx$^$n$+$a$\_($n$-1)$x$*($n$-1)+$a$\_($n$-2)$x$^($n$-2)+...+$a$\_1$x$^1+$a$\_0$