code: public Map<String, Map<Long, FeatureShape>> getTables(String database) {
  
          Map<String, Map<Long, FeatureShape>> tables = databases.get(database);
          if (tables == null) {
              tables = new HashMap<>();
              databases.put(database, tables);
          }
          return tables;
      }
docs: Get the mapping between tables and feature ids for the database
  
  @param database GeoPackage database
  @return tables to features ids mapping
  @since 3.2.0