code: public void add(IWord word)
      {
          Item item = trie.get(word.getValue());
          if (item == null)
          {
              item = new Item(word.getValue(), word.getLabel());
              trie.put(item.key, item);
          }
          else
          {
              item.addLabel(word.getLabel());
          }
      }
docs: 向词典中加入一个词语
  
  @param word 词语