[aspectj-users] Can not retrieve information from the passing parameters

["lily lily" <lixiaojiao@xxxxxxxxxxx>]

Hi:
I am working on a web application of a database. JSPs provide the 
presentation logic, Java Servlets provide control to the flow of data, Java 
Beans do the actual data access to the database. Now I want to add an access 
control to it using aspectJ.

The accsss control code is like this:

---------------------------------------------------------------------------------------
package tables;

import java.io.*;
import java.util.*;

aspect AccessControl perthis(checkpoint(Vector))
{
pointcut checkpoint(Vector v): execution(public String 
project.insert(Vector)throws ClassNotFoundException) && args(v);

String around(Vector v): checkpoint(v)
{
  check the access availability, if true
    return proceed(v);
 otherwise,
   return "NotAllowed";
}
}
--------------------------------------------------------------------------------------

The problem is that when I do the access control, I need some user 
information like user's  name, user's ID to determine the result. But I 
could not get such information from the passing parameters of method 
project.insert. I could add another parameter called say 'UserInfo' to the 
project.insert method in order to retrieve the user information. But this is 
not what I want. I do not want to touch any of the project.insert code. This 
will make Plugging and Unplugging the access control easily in the furture. 
The programmer of method project.insert does not even realize that the 
access control exists.

Is this possible? How to solve it?

Thanks in advance.

Lily

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