code: public boolean exists(VirtualFile mountPoint, VirtualFile target) {
          final ZipNode zipNode = rootNode.find(mountPoint, target);
          if (zipNode == null) {
              return false;
          } else {
              final File cachedFile = zipNode.cachedFile;
              return cachedFile == null || cachedFile.exists();
          }
      }
docs: {@inheritDoc}