docs: public IndexSchema getSolrSchema() {
  
          if (m_schema == null) {
              try (FileInputStream fis = new FileInputStream(getSolrSchemaFile())) {
                  InputSource solrSchema = new InputSource(fis);
                  m_schema = new IndexSchema(getSolrConfig(), SOLR_SCHEMA_NAME, solrSchema);
              } catch (IOException e) {
                  CmsConfigurationException ex = new CmsConfigurationException(
                      Messages.get().container(
                          Messages.LOG_SOLR_ERR_SCHEMA_XML_NOT_FOUND_1,
                          getSolrSchemaFile().getPath()),
                      e);
                  LOG.error(ex.getLocalizedMessage(), ex);
              }
          }
          return m_schema;
      }