删除List中指定的元素

CopyOnWriteArrayList是ArrayList的一个线程安全的变体实现，即可在多线程并发环境中使用

        List<Map<String, Object>> allUsers = (List<Map<String, Object>>) userService.getAllUsers().get("allUser");
        CopyOnWriteArrayList allUser = new CopyOnWriteArrayList(allUsers);
        Iterator<Map<String, Object>> iter = allUser.iterator();
        while (iter.hasNext()) {
            Map<String, Object> map = iter.next();
            Iterator<Map.Entry<String, Object>> iterSub = map.entrySet().iterator();
            while (iterSub.hasNext()) {
                Map.Entry entry = iterSub.next();
                if(entry.getKey().equals("username")){
                    logger.info("username： " + entry.getKey());
                    if (entry.getValue().equals("admin")){
                        logger.info("admin： " + entry.getValue());
                        allUser.remove(map);
                     }
                }
            }
        }

        logger.info("allUser： " + allUser);