code: public void merge(SubjectAware subjectAware)
    {
      merged = true;
  
      String username = subjectAware.username();
  
      if (username.length() > 0)
      {
        this.username = username;
      }
  
      String password = subjectAware.password();
  
      if (password.length() > 0)
      {
        this.password = password;
      }
  
      String configuration = subjectAware.configuration();
  
      if (configuration.length() > 0)
      {
        this.configuration = configuration;
      }
    }
docs: Method description
  
  
  @param subjectAware