code: public void setSearchIndex(CmsSearchIndex index) throws CmsIllegalArgumentException {
  
          if (index == null) {
              throw new CmsIllegalArgumentException(Messages.get().container(Messages.ERR_INDEX_NULL_0));
          }
          m_index = index;
      }
docs: Sets the search index to use for the search. <p>
  
  @param index the search index to use for the search to set.
  
  @throws CmsIllegalArgumentException if null is given as argument