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Re: [aspectj-users] Bizarre behavior with args pointcut 
Wes Isberg wrote:
this(), target(), and args() always (act as if they) do a dynamic instance-of check on the object. The semantics are the same whether the object is bound to a variable or not. (And as per 
instanceof, a null object will not match.)
Is there documention saying exactly what this(), target(), ... do? The following example would suggest they do in fact do an 'instanceof' check. 

//----- begin code -----
public class CL {
  public static void main(String[] args) throws Exception {
    out(new MyLoader().findClass("CL$C").newInstance().toString());
    out("------------------------------------------------------------");
    out(new C() {public void f(){}}.toString());
  }

  static void out(Object s) {System.out.println(s);}

  public static class C {
    public C() {}
    public void f() { System.out.println("C.f"); }
  }

  static aspect A {
    before(): target(C) { out("before: " + thisJoinPoint); }
  }

  static class MyLoader extends ClassLoader {
    protected Class findClass(String name)
    throws ClassNotFoundException {
      return super.defineClass(name, Cbytes, 0, Cbytes.length);
    }
  }

  final static byte[] Cbytes = new byte[] {
    -54,-2,-70,-66,0,0,0,47,0,32,7,0,2,1,0,
    4,67,76,36,67,7,0,4,1,0,16,106,97,118,
    97,47,108,97,110,103,47,79,98,106,101,99,116,1,0,
    1,102,1,0,3,40,41,86,1,0,4,67,111,100,
    101,1,0,15,76,105,110,101,78,117,109,98,101,114,
    84,97,98,108,101,12,0,10,0,11,1,0,3,111,
    117,116,1,0,21,76,106,97,118,97,47,105,111,47,80,
    114,105,110,116,83,116,114,101,97,109,59,9,0,13,0,
    9,7,0,14,1,0,16,106,97,118,97,47,108,97,110,
    103,47,83,121,115,116,101,109,8,0,16,1,0,3,67,
    46,102,12,0,18,0,19,1,0,7,112,114,105,110,
    116,108,110,1,0,21,40,76,106,97,118,97,47,108,
    97,110,103,47,83,116,114,105,110,103,59,41,86,10,0,
    21,0,17,7,0,22,1,0,19,106,97,118,97,47,105,
    111,47,80,114,105,110,116,83,116,114,101,97,109,1,0,
    6,60,105,110,105,116,62,12,0,23,0,6,10,0,3,
    0,24,1,0,10,83,111,117,114,99,101,70,105,108,
    101,1,0,7,67,76,46,106,97,118,97,1,0,12,73,
    110,110,101,114,67,108,97,115,115,101,115,7,0,30,1,
    0,2,67,76,1,0,1,67,0,33,0,1,0,3,0,
    0,0,0,0,2,0,1,0,5,0,6,0,1,0,7,
    0,0,0,37,0,2,0,1,0,0,0,9,-78,0,12,
    18,15,-74,0,20,-79,0,0,0,1,0,8,0,0,0,
    10,0,2,0,0,0,10,0,8,0,10,0,1,0,23,
    0,6,0,1,0,7,0,0,0,33,0,1,0,1,0,
    0,0,5,42,-73,0,25,-79,0,0,0,1,0,8,0,
    0,0,10,0,2,0,0,0,9,0,4,0,9,0,2,
    0,26,0,0,0,2,0,27,0,28,0,0,0,10,0,1,0,1,0,29,0,31,0,9,
  };
}
//----- end code -----


This prints out:

  jpalm@Machine ~/src/aspectj
  $ ajc CL.java; ajava CL
  CL$C@1172e08
  ------------------------------------------------------------
  before: initialization(CL.C())
  before: execution(CL.C())
  before: initialization(CL.1())
  before: execution(CL.1())
  before: call(String java.lang.Object.toString())
  CL$1@19f953d

and doesn't get the advice on the second instance.

Jeff




--
Jeffrey Palm --> http://www.ccs.neu.edu/home/jpalm

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