code: public Whitelist addTags(String... tags) {
          Validate.notNull(tags);
  
          for (String tagName : tags) {
              Validate.notEmpty(tagName);
              tagNames.add(TagName.valueOf(tagName));
          }
          return this;
      }
docs: Add a list of allowed elements to a whitelist. (If a tag is not allowed, it will be removed from the HTML.)
  
  @param tags tag names to allow
  @return this (for chaining)