code: public void buildSummary(XMLNode node, Content moduleContentTree) throws DocletException {
          Content summaryContentTree = moduleWriter.getSummaryHeader();
          buildChildren(node, summaryContentTree);
          moduleContentTree.addContent(moduleWriter.getSummaryTree(summaryContentTree));
      }
docs: Build the module summary.
  
  @param node the XML element that specifies which components to document
  @param moduleContentTree the module content tree to which the summaries will
  be added
  @throws DocletException if there is a problem while building the documentation