code: private final void _declareNotReleasable() throws SevereMessageStoreException
      {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "_declareNotReleasable");
  
          if (_isStorageManaged)
          {
              _itemCache.unmanage(this);
          }
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "_declareNotReleasable");
      }
docs: inform the cache (if there is one) that the item owned by this
  link is not releasable.
  
  @throws SevereMessageStoreException