import java.lang.annotation.*; @Retention(RetentionPolicy.RUNTIME) @interface Colored { String color(); } @Colored(color="yellow") public class AtTarget1 { public static void main(String[]argv) { new AtTarget1().m(); } @Colored(color="red") public void m() { System.err.println("method"); } } aspect X { int adviceExecutions = 0; before(Colored c): call(* *(..)) && !within(X) && @target(c) { System.err.println(c.color()); adviceExecutions++; if (!c.color().equals("yellow")) throw new RuntimeException("Color should be yellow"); if (adviceExecutions>1) throw new RuntimeException("Advice shouldn't be called more than once"); } }