code: public void setParamLanguage(String language) {
  
          if (language != null) {
              if (m_paramSelectedLanguages == null) {
                  m_paramSelectedLanguages = new HashSet<String>();
              }
              // add all available values here
              String[] values = getParameterMap().get(PARAM_LANGUAGE);
              for (int i = 0; i < values.length; i++) {
                  m_paramSelectedLanguages.add(decodeParamValue(PARAM_LANGUAGE, values[i]));
              }
          }
      }
docs: Sets the list of selected languages.<p>
  
  @param language a selected language