code: @Override
    public boolean doList(String path, final ResourceFilter filter)
    {
      boolean isDirectory = false;
  
      ResourceFilter newFilter = new ResourceFilter()
      {
        @Override
        public boolean accept(Resource resource)
        {
          return filter.accept(new ResourceChain(ResourceProviderChain.this,
                                                 resource.getPath(),
                                                 resource));
        }
      };
  
      for(InternalResourceProvider resourceProvider : _resourceProviders)
      {
        isDirectory |= resourceProvider.doList(path, newFilter);
      }
  
      return isDirectory;
    }
docs: If the path denotes a directory, then it will return all resources that are contained in the
  directory.
  
  @param path   the path to the resource
  @param filter the filter to include only some resources in the result
  @return <code>true</code> if it was a directory, <code>false</code> otherwise