code: protected PBKDF2 getEngine(PBKDF2Parameters parameters) {
          PBKDF2 engine = newInstance(engineClassName, PBKDF2.class);
          if( engine != null ) {
          	engine.setParameters(parameters);
          }
          return engine;
      }
docs: Factory method: instantiate the PBKDF2 engine. Override or change the
  class via attribute.
  
  @param parameters Parameters
  @return Engine object. On error/exception, this method registers the
  exception via {{@link #setValidateError(Throwable)} and returns
  <code>null</code>.