code: @SuppressWarnings("unchecked")
      public <T extends XPathBuilder> T setCls(final String cls) {
          this.cls = cls;
          return (T) this;
      }
docs: <p><b>Used for finding element process (to generate xpath address)</b></p>
  <p>Find element with <b>exact math</b> of specified class (equals)</p>
  
  @param cls class of element
  @param <T> the element which calls this method
  @return this element