code: @Override
      public void load(String persistenceUnit, Map<String, Object> puProperties)
      {
          setPersistenceUnit(persistenceUnit);
  
          // Load Client Specific Stuff
          logger.info("Loading client metadata for persistence unit : " + persistenceUnit);
          loadClientMetadata(puProperties);
  
          // initialize the client
          logger.info("Initializing client for persistence unit : " + persistenceUnit);
          initialize(puProperties);
  
          // Construct Pool
          logger.info("Constructing pool for persistence unit : " + persistenceUnit);
          connectionPoolOrConnection = createPoolOrConnection();
      }
docs: Load.
  
  @param persistenceUnit
  the persistence unit