code: public void removeTag(String tagName) {
      for (int i = 0; i < tags.size(); i++) {
        if (tags.get(i).getName().equals(tagName)) {
          tags.remove(i);
          if (hashTagsName.containsKey(tagName))
            hashTagsName.remove(tagName);
          if (hashTagsId.containsKey(TiffTags.getTagId(tagName)))
            hashTagsId.remove(TiffTags.getTagId(tagName));
          i--;
        }
      }
    }
docs: Removes the tag.
  
  @param tagName the tag name