code: private void setNext()
      {
          initial = true;
          try
          {
              if (next != null)
              {
                  jar.closeEntry();
              }
              next = null;
  
              do
              {
                  next = jar.getNextJarEntry();
              }
              while (next != null && (next.isDirectory() || (filter == null || !filter.accepts(next.getName()))));
  
              if (next == null)
              {
                  close();
              }
          }
          catch (IOException e)
          {
              throw new ResourceReadingException("Failed to browse jar:", e);
          }
      }
docs: Sets the next.