Subclassing nested (private ns) classes at runtime

A question for the AVM2 engineers here.
I am the author of
asmock, a dynamic object
mocking framework, and am looking at a few features to add before
1.0. One of the biggest features I'd like to support is the ability
to mock a "nested" (private namespace) class.
I know that subclassing a nested class outside the "code
file" is illegal, but I have assumed that the AVM will let me do it
as long as I setup the DoABC tag correctly.
Based on dumps of valid SWFs that do this, there does not
seem to be anything special about the classes. Both the child and
the parent are declared with a private ns multiname (0x05) and the
members are declared as public traits of the class. The ns used is
copied directly from the parent (for nested classes), and is always
"Filename.as$number". However, during loadBytes, I get a
ValidateError: "Class
MockRepositoryNestedClassIntegrationFixture.as$452::NestedClass
could not be found".
Is there anything I might have missed? Or, alternatively, is
there an explicit AVM restriction that nested classes can only be
subclassed within the SWF they were loaded from?
Many thanks,
Richard

"richard.szalay" <[email protected]> wrote
in message
news:gm3rfo$f0h$[email protected]..
>A question for the AVM2 engineers here.
>
> I am the author of
http://asmock.sourceforge.net/,
a dynamic object
> mocking
> framework, and am looking at a few features to add
before 1.0. One of the
> biggest features I'd like to support is the ability to
mock a "nested"
> (private
> namespace) class.
>
> I know that subclassing a nested class outside the "code
file" is illegal,
> but
> I have assumed that the AVM will let me do it as long as
I setup the DoABC
> tag
> correctly.
>
> Based on dumps of valid SWFs that do this, there does
not seem to be
> anything
> special about the classes. Both the child and the parent
are declared with
> a
> private ns multiname (0x05) and the members are declared
as public traits
> of
> the class. The ns used is copied directly from the
parent (for nested
> classes),
> and is always "Filename.as$number". However, during
loadBytes, I get a
> ValidateError: "Class
>
MockRepositoryNestedClassIntegrationFixture.as$452::NestedClass
could not
> be
> found".
>
> Is there anything I might have missed? Or,
alternatively, is there an
> explicit
> AVM restriction that nested classes can only be
subclassed within the SWF
> they
> were loaded from?
I think you're more likely to find someone who knows the
framework and the
player in this kind of detail on the flexcoders yahoo group.

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>
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         URL urlNewBase = new URL("jar:" + urlBase.toExternalForm() + "!/" );
         File fURLControl = new File(CSystem.GetBasePath() + "/Research/bin/controls.jar");
         URL urlControl = new URL(fURLControl.toURL(),"");
         URL urlNewControl = new URL("jar:" + urlControl.toExternalForm() + "!/" );
         File fURLUtil = new File(CSystem.GetBasePath() + "/Research/bin/utlities.jar");
         URL urlUtil= new URL(fURLUtil.toURL(),"");
         URL urlNewUtil = new URL("jar:" + urlUtil.toExternalForm() + "!/" );
         // Determine where to look
         URL[] urlList = null;
         if(GetMainFrame().m_isStandalone == false) {
            // From a browser
            CSystem.PrintDebugMessage("Running as an applet");
            if(GetMainFrame().m_bOnLineMode == true) {
               // On line
               CSystem.PrintDebugMessage("*** On Line Mode ***");
               urlList = new URL[2];
               urlList[0] = urlNew;
               urlList[1] = urlNew2;
            else {
               // Off line
               CSystem.PrintDebugMessage("*** Off Line Mode ***");
               urlList = new URL[4];
               urlList[0] = urlNew;
               urlList[1] = urlNewBase;
               urlList[2] = urlNewControl;
               urlList[3] = urlNewUtil;
          else {
             CSystem.PrintDebugMessage("*** Stand Alone Mode ***");
             urlList = new URL[1];
             urlList[0] = urlNew;
CSystem.PrintDebugMessage("Question file/path: " + GetMainFrame().m_strQuestionnaireFileName);
        // Set the wait cursor
        GetMainFrame().SetWaitCursor();
        // Get a reference to the applets own classloader
        Class myClass = getClass();
        ClassLoader appletClassLoader = myClass.getClassLoader();
        // Call our multi-jar class loader
        JarClassLoader jarLoader = new JarClassLoader(urlList,appletClassLoader);
CSystem.PrintDebugMessage("CPM Test - passed Jar Loader" + jarLoader.toString());
         // Load the classname from the jarfile
         try
              cClass = jarLoader.loadClass(classname);
         catch(ClassNotFoundException cnfe)
            Object[] optionsConfirm = { "Ok" };
            JOptionPane.showOptionDialog(GetMainFrame(),"Questionnaire file is either damaged or has been tampered with.", "Questionnaire File Error",
            JOptionPane.DEFAULT_OPTION, JOptionPane.WARNING_MESSAGE, null, optionsConfirm, optionsConfirm[0]);
            GetMainFrame().m_strQuestionnaireFileName = "";
            // Clear the wait cursor
            GetMainFrame().ClearWaitCursor();
            return null;
         Class cSuperclass = cClass.getSuperclass();
CSystem.PrintDebugMessage("Test Superclass type is: " + cSuperclass.toString());
         Object o = cClass.newInstance();
CSystem.PrintDebugMessage("Test plain class type is: " + o.toString());
         // Never remove this line of code
         // without it, a crafty user could use our load routine
         // to load/and run some nasty code
         // This test makes SURE that *ONLY* questionnaires get opened
         // and their methods get called
         if(o instanceof com.cpm.common.base.CBaseQuestionnaireFile)
            // Create the object
CSystem.PrintDebugMessage("Test Is instance of CBaseQuestionnaireFile");
CSystem.PrintDebugMessage("CPM Test - Casting to Base Class");
            questBase = (com.cpm.common.base.CBaseQuestionnaireFile)o;
CSystem.PrintDebugMessage("CPM Test - Getting languages from questionnaire");
            GetMainFrame().GetLanguagesFromQuestionnaire(questBase);
CSystem.PrintDebugMessage("CPM Test - Setting locale from Questionnaire selection");
            questBase.SetQuestionnaireLocale(GetMainFrame().m_locale);
CSystem.PrintDebugMessage("CPM Test - Initializing Questionnaire");
            questBase.Initialize();
            questBase.InitializeCards();
          else
            Object[] optionsConfirm = { "Ok" };
            JOptionPane.showOptionDialog(GetMainFrame(),"Questionnaire file is either damaged or has been tampered with.", "Questionnaire File Error",
            JOptionPane.DEFAULT_OPTION, JOptionPane.WARNING_MESSAGE, null, optionsConfirm, optionsConfirm[0]);
            GetMainFrame().m_strQuestionnaireFileName = "";
            // Clear the wait cursor
            GetMainFrame().ClearWaitCursor();
            return null;
      catch (Exception e)
          exDialog.showForThrowable(e.toString(),e);
     // Clear the wait cursor
     GetMainFrame().ClearWaitCursor();
     // Set MouseListener Pointer
//     questBase.SetMouseListenerPointer(GetMainFrame().m_mouseListener);
     return questBase;
   }

Is it possible to instantiate arbitrary classes at runtime??

Hi,
I was wondering if it is possible to instantiate an arbitrary class at runtime using its class name.
My plan is to have a collection of java classes in a folder, which could be instantiated and have their member methods called. This collection of classes however, could change at any time. I'd like to be able to specify which class to work with at runtime, using a string containing the class name to identify it.
Is this possible using java?? If so, how?
Thanks in advance.

It's called reflection.
Class someClass = Class.forName("some.package.SomeClass");
...

Could not initialize class coldfusion.runtime.report.Report

I have inherited an application that contains a number of
reports. This application was developed on our CF7 server, and when
we upgraded, the application was copied to 8, but not fully tested.
Now, when we request the reports, we get the following errors (this
is a Flex application):
(mx.rpc::Fault)#0
errorID = 0
faultCode = "Server.Processing"
faultDetail = (null)
faultString = "Could not initialize class
coldfusion.runtime.report.Report"
message = "faultCode:Server.Processing faultString:'Could
not initialize class coldfusion.runtime.report.Report'
faultDetail:'null'"
name = "Error"
rootCause = (null)
My searching for a solution has not been successful on
Google. Has anyone experienced this error and been able to fix it?
I'm at a loss on what to do next, and as the app is in production,
I have some upset clients over this.
Thanks!!
Jenn

I can't find anything further on this error after much
research. I'm getting the problem when I try to run any report on a
live web server (hosted site), even though it runs fine in the
development environment. My hosting company could only suggest that
the problem could lie with the fact they have RDS disabled;
however, although the Report Builder requires RDS, running uploaded
.cfr reports from the cfreport tag shouldn't. If anyone solves this
I'd be most grateful for the information to be posted.

Subclassing nested (private ns) classes at runtime

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