element cannot be mapped to a null key

使用jdk8的stream流分组报错

Map> userInfoVoMap = userInfoVoList.stream().collect(Collectors.groupingBy(UserInfoVo::getTenantId));

分组字段的值不能为null

添加null判断

Map> userInfoVoMap = userInfoVoList.stream()
			.filter(map->map.getTenantId()!=null)
			.collect(Collectors.groupingBy(UserInfoVo::getTenantId));