output: #fixed code
                                  public String getConceptNetUrl() {
          String urlFromConfigOrDefault = (String)getConfiguration().getSettingValueFor(CONFIG_KEY_URL);
  
          return urlFromConfigOrDefault == null
                  ? DEFAULT_CONCEPTNET_URL
                  : urlFromConfigOrDefault;
      }
input: #vulnerable code 
                                  public String getConceptNetUrl() {
          String urlFromConfigOrDefault = getConfiguration().getSettingValueFor(CONFIG_KEY_URL).toString();
  
          return urlFromConfigOrDefault == null
                  ? DEFAULT_CONCEPTNET_URL
                  : urlFromConfigOrDefault;
      } 
                              #location 2 
                              #vulnerability type NULL_DEREFERENCE