code: public int doEndTag() throws JspException
      {
          // if there were errors lets report them.
          if (hasErrors()) {
              reportErrors();
          }
  
          // Get the script reporter
          IScriptReporter sr = getScriptReporter();
          if (sr != null) {
              //if (!sr.isInitScriptWritten()) {
              //    String s = Bundle.getString("Tags_ClientReqScriptHeader", null);
              //    registerTagError(s, null);
              //}
  
              // write out any errors
              ErrorHandling.reportCollectedErrors(pageContext, this);
  
              // write out the script before the end tag.
              sr.writeScript(_writer);
  
              if (sr instanceof Html) {
                  Html htmlSr = (Html) sr;
                  if (htmlSr.getIdScope() != null) {
                      htmlSr.endScope(_writer);
                  }
              }
          }
  
          if (_idScript != null)
              write(_idScript);
  
          _br.doEndTag(_writer);
  
          // Evaluate the remainder of this page
          localRelease();
          return EVAL_PAGE;
      }
docs: Render the button.
  @throws JspException if a JSP exception has occurred