code: public String buildCheckRecursive() {
  
          StringBuffer retValue = new StringBuffer(256);
  
          // show the checkbox only for folders
          if (isOperationOnFolder()) {
              retValue.append("<tr>\n\t<td colspan=\"3\" style=\"white-space: nowrap;\" unselectable=\"on\">");
              retValue.append("<input type=\"checkbox\" name=\"");
              retValue.append(PARAM_RECURSIVE);
              retValue.append("\" value=\"true\">&nbsp;");
              retValue.append(key(Messages.GUI_TOUCH_MODIFY_SUBRESOURCES_0));
              retValue.append("</td>\n</tr>\n");
          }
          return retValue.toString();
      }
docs: Creates the "recursive" checkbox for touching subresources of folders.<p>
  
  @return the String with the checkbox input field or an empty String for folders.