利用lambda表达式对map集合过滤求和

Long messageTask = taskResult.stream().filter(e -> e.get("taskTypeId").toString().equals("202")|| e.get("taskTypeId").toString().equals("206"))
        .collect(Collectors.summarizingInt(e -> Integer.valueOf(e.get("totalOrderCount").toString()))).getSum();

原文：https://www.cnblogs.com/JasonKong/p/11454763.html