I'm trying to implement a cache viewer based on some of your code samples from the chapter. In the GetCache method I get a runtime exception of null reference from the following code.

            FieldInfo fieldCacheInt = currentContext.Cache.GetType().GetField("_cacheInt ernal",
                BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.GetField);

            object cacheInt = fieldCacheInt.GetValue(currentContext.Cache);

************************************************** ****************
field entries is always null
************************************************** ****************
FieldInfo fieldEntries = cacheInt.GetType().GetField("_entries",
                            BindingFlags.NonPublic | BindingFlags.Instance);
************************************************** ****************

            Hashtable hashEntries = fieldEntries.GetValue(cacheInt) as Hashtable;
            Hashtable hashCopy = new Hashtable(hashEntries.Count);