code: public static HtmlTree A(String ref, Content body) {
          HtmlTree htmltree = new HtmlTree(HtmlTag.A, nullCheck(body));
          htmltree.addAttr(HtmlAttr.HREF, encodeURL(ref));
          return htmltree;
      }
docs: Generates an HTML anchor tag.
  
  @param ref reference url for the anchor tag
  @param body content for the anchor tag
  @return an HtmlTree object