code: public void addReaction(Emoji emoji, boolean you) {
          Optional<Reaction> reaction = reactions.stream().filter(r -> emoji.equalsEmoji(r.getEmoji())).findAny();
          reaction.ifPresent(r -> ((ReactionImpl) r).incrementCount(you));
          if (!reaction.isPresent()) {
              reactions.add(new ReactionImpl(this, emoji, 1, you));
          }
      }
docs: Adds an emoji to the list of reactions.
  
  @param emoji The emoji.
  @param you Whether this reaction is used by you or not.