code: @Override
      protected void initializeImpl()
      {
          //setup connection factory
          String className=this.getConfigurationValue(FaxClientSpiConfigurationConstants.CONNECTION_FACTORY_CLASS_NAME_PROPERTY_KEY);
          if(className==null)
          {
              className=HylaFAXClientConnectionFactoryImpl.class.getName();
          }
          this.connectionFactory=this.createHylaFAXClientConnectionFactory(className);
          if(this.connectionFactory==null)
          {
              throw new FaxException("HylaFAX connection factory is not available.");
          }
      }
docs: This function initializes the fax client SPI.