code: public static String stringSetToTextArea(Set<String> elements) {
  		StringBuilder sb = new StringBuilder();
  		if (elements != null) {
  			for (String element : elements) {
  				sb.append(element);
  				sb.append(TEXTAREA_ELEMENTS_SEPARATOR);
  			}
  		}
      	int length = sb.length();
  		return sb.substring(0, length > 0 ? length - 1 : 0);
  	}
docs: <p>stringSetToTextArea.</p>
  
  @param elements a {@link java.util.Set} object.
  @return a {@link java.lang.String} object.