code: public boolean isModelGroupEntry(CmsUUID entryId) {
  
          return m_modelPageTreeItems.containsKey(entryId) && m_modelPageTreeItems.get(entryId).isModelGroup();
      }
docs: Returns if the given entry is a model group page.<p>
  
  @param entryId the entry id
  
  @return <code>true</code> if the given entry is a model group page