code: public void displayDialog() throws Exception {
  
          if (getAction() == ACTION_CANCEL) {
              actionCloseDialog();
          }
          CmsFile resource1 = CmsResourceComparisonDialog.readFile(
              getCms(),
              new CmsUUID(getParamId1()),
              getParamVersion1());
          CmsFile resource2 = CmsResourceComparisonDialog.readFile(
              getCms(),
              new CmsUUID(getParamId2()),
              getParamVersion2());
          String linkTarget1 = new String(resource1.getContents());
          String linkTarget2 = new String(resource2.getContents());
          JspWriter out = getJsp().getJspContext().getOut();
          out.println(dialogBlockStart(key(Messages.GUI_COMPARE_CONTENT_0)));
          out.println(dialogContentStart(null));
          out.println("<table cellpadding='0' cellspacing='0' border='0' class='maxwidth'><tr align='center'><th>");
          out.println(
              key(
                  Messages.GUI_COMPARE_VERSION_1,
                  new String[] {CmsHistoryListUtil.getDisplayVersion(m_paramVersion1, getLocale())}));
          out.println("</th><th>");
          out.println(
              key(
                  Messages.GUI_COMPARE_VERSION_1,
                  new String[] {CmsHistoryListUtil.getDisplayVersion(m_paramVersion2, getLocale())}));
          out.println("</th></tr>");
          out.print("<tr><td><a href=\"");
          out.print(linkTarget1);
          out.print("\">");
          out.print(linkTarget1);
          out.print("</a>");
          out.print("</td><td width='50%'>\n");
          out.print("<a href=\"");
          out.print(linkTarget2);
          out.print("\">");
          out.print(linkTarget2);
          out.print("</a>");
          out.println("</td></td></table>");
          out.println(dialogBlockEnd());
          out.println(dialogContentEnd());
          out.println(dialogEnd());
          out.println(bodyEnd());
          out.println(htmlEnd());
      }
docs: Performs the dialog actions depending on the initialized action and displays the dialog form.<p>
  
  @throws Exception if writing to the JSP out fails