docs: public int doEndTag() throws JspException {
          String msg;
  
          try {
              Iterator<String> iterator;
              String parameterName;
  
              // -- Harald K 20020726
              // Include the page, in place
              //getDispatcher().include(getRequest(), getResponse());
              addParameter(PAGE_CONTEXT, pageContext); // Will be cleared later
              pageContext.include(page);
  
              // Remove all the parameters that were added to the request scope
              // for this insert tag.
              iterator = parameterNames.iterator();
  
              while (iterator.hasNext()) {
                  parameterName = iterator.next();
  
                  getRequest().removeAttribute(parameterName);
              }
  
              iterator = oldParameters.keySet().iterator();
  
              // Restore the parameters we temporarily replaced (if any).
              while (iterator.hasNext()) {
                  parameterName = iterator.next();
  
                  getRequest().setAttribute(parameterName, oldParameters.get(parameterName));
              }
  
              return super.doEndTag();
          }
          catch (IOException ioe) {
              msg = "Caught an IOException while including " + page
                      + "\n" + ioe.toString();
              log(msg, ioe);
              throw new JspException(msg);
          }
          catch (ServletException se) {
              msg = "Caught a ServletException while including " + page
                      + "\n" + se.toString();
              log(msg, se);
              throw new JspException(msg);
          }
      }