Method putMessage

drg_group/qingdao_2023/Messages.java:12–14

(String index,String message)

        messages.put(index, new ArrayList<String>());
    }
    public void putMessage(String index,String message){
        messages.get(index).add(message);
    }
    public boolean existMessage(String index,String message){
        return messages.get(index).contains(message);
    }