/* illustrating the difference between 'this' and 'target' pointcuts */

class A
{
    public void f() { System.out.println("don't give me an f"); }
}
class B
{
    public void g(A n)
    {
	n.f();
    }
}

public class thistarget
{
    public static void main(String[] av)
    {
	A n = new A();
	B p = new B();
	// 'this(x) pointcut captures value of 'this' in this context.
	p.g(n); // target is the target object, p, that call is made on.
    }
}

// should be in separate file...
aspect thisandtarget
{
    before(A x, B y): call(void A.f()) && this(y) && target(x)
	{
	    System.out.println("Object "+y+" is calling f on object "+x);
	}

    void around(thistarget instance): call(void B.g(..)) && withincode(static void thistarget.main(..) && this(instance)
								       {   System.out.println("about to call g from main"); proceed(instance); }

}

/*  output:
Object B@677327b6 is calling f on object A@14ae5a5
don't give me an f

Question: would the around advice run for the call to p.g from main? 

Answer: NO! because main is static, which means there is no 'this'.
Try System.out.println(this); from main and see what happens.

Don't use 'this' pointcut with 'execution' instead of call.
*/