ApplicationError when trying to implement an edited version of the Secure module

I'm implementing an edited version of the Secure controller, default in the latest Play Framework.

I have read several times that, if you want to customize the Secure behaviour, you're better off copying the source of the Secure module, and start customizing it.

So I did, and after editing the needed dependencies I received following error:

    Execution exception
NullPointerException occured : null

In /app/controllers/SecureController.java (around line 194)

190:
                 security = classes.get(0);
191:
             }
192:
             if(security==null)System.out.println("security is null");
193:
             try {
194:
                 return Java.invokeStaticOrParent(security, m, args);
195:
             } catch(InvocationTargetException e) {
196:
                 throw e.getTargetException();
197:
             }
198:
         }
199:

200:
     }

The first logic conclusion to jump to is: there are no classes that implement the needed Secure$Security inner class. But there most certainly is a subclass, so I was wondering how this error can be fixed.

A debugging session learns that the classes.get(0) does contain the class that has the @With annotation. So the null pointer exception must be caused by something within the class that contains the @With(SecureController). But I left that class just th开发者_JAVA百科e way it was, I just edited the reference within the With annotation.

So my guess is that somehow, there is a null pointer within the class implementation. But even when I implement default behaviour, without any references, it still generates a nullpointerexception.

EDIT: I found the cause of this error, but the 'why' isn't clear. This line is found in the implementation of the authenticate(...) method in the subclass of SecureController$Security:

flash.put("url", request.url);

Why does this fail?

I understand this situation may be very hard to reproduce, but I was wondering if someone already experienced the same issue.

Thanks for the help (on many Play! related topics) so far.

---

the Scope.Flash class does not allow you to store null values. Perhaps you unset or failed to set request.url elsewhere in your modifications?