Classloading a class that depends on non-existent classes..

hi,
an application i am working on needs to be run in an environment where it will dynamically load existing classes (which i have no control over) that might depend on API that we no longer ship. I don't want to reimplement the API so instead would like to detect and ignore the class completely.
it would be possible to just ignore all classes, but this throws the baby out with the bathwater - its better to be able to do as much as possible and just ignore those classes we can't load at all
is there a way of detecting whether a class you are loading depends on classes that aren't currently loaded using the standard library API? (using jreversepro you can get access to the entire constant pool but i'd prefer to avoid this if possible)
the language. spec. says that a ClassNotFoundException can be thrown lazily (i think this is also how the sun vms work?) - ie not until the reference is actually used
ClassLoader.loadClass(String fqn, boolean resolveBindings) looks the most promising but the lang. spec. implies it won't actually moan about this?
any help appreciated,
thanks,
asjf

Try loading the class with the java.lang.Class object. This way you can catch the noClassDefFound error.
I've used this to determine that they aren't using Microsofts VM. I'm not certain that it will work in your case, but here is my VM example....
try
               Class SystemVersionManager;
               Object VMVersion;
               Method getVMVersion;
               Method getProperty;
               Object[] inc = {"BuildIncrement"};
               String a = "";
               Class[] arg = {a.getClass()};
               System.out.println("Running IE?");
               SystemVersionManager = Class.forName("com.ms.util.SystemVersionManager");
               getVMVersion = SystemVersionManager.getMethod("getVMVersion",null);
               VMVersion = getVMVersion.invoke(SystemVersionManager,null);
               getProperty = VMVersion.getClass().getMethod("getProperty",arg);
               System.out.println("You are running VM level " + getProperty.invoke(VMVersion,inc));
          catch (Exception e)
               System.out.println("You're not using Microsofts VM.");
          }It invokes the com.ms.util.SystemVersionManager and uses its getProperty() method on it.

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Revision: 16929
Revision: 16929
Author:   [email protected]
Date:     2010-07-15 07:38:44 -0700 (Thu, 15 Jul 2010)
Log Message:
Add a class that will register the required class aliases in the event the mxml compiler generation [RemoteClass(alias="")] code is not called because an application does not use the Flex UI framework.
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