code: private static List<Column> getAncestorColumns(Resource currentResource, Resource rootResource) {
      List<Column> columns = new ArrayList<>();
      List<Resource> ancestors = getAncestors(currentResource, rootResource);
      for (int i = 0; i < ancestors.size(); i++) {
        Resource r = ancestors.get(i);
  
        String activeId;
        if (i < ancestors.size() - 1) {
          activeId = ancestors.get(i + 1).getPath();
        }
        else {
          activeId = currentResource.getPath();
        }
  
        Column column = new Column()
            .columnId(r.getPath())
            .lazy(true)
            .activeId(activeId);
        columns.add(column);
      }
      return columns;
    }
docs: Generate column for each ancestor.
  @param currentResource Current resource
  @param rootResource Root resource
  @return Columns