code: @Override
    public boolean doList(String path, ResourceFilter filter)
    {
      if(_root == null)
        return false;
  
      RAMEntry entry = _root.getEntryByPath(path);
  
      if(entry instanceof RAMDirectory)
      {
        RAMDirectory ramDirectory = (RAMDirectory) entry;
        for(RAMEntry ramEntry : ramDirectory.ls())
        {
          String resourcePath = PathUtils.addPaths(path, ramEntry.name());
          filter.accept(new RAMResource(this,
                                        getFullPath(resourcePath),
                                        resourcePath));
        }
        return true;
      }
      else
        return false;
    }
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
  @throws IOException if there is an error accessing the resource