Java8新特性-关于List的操作

发布时间 2023-06-02 17:33:13作者: DAYTOY-105

1 Java获取List对象的某属性组成新的List

List<String> list = signPicsDtoEntityList.stream().map(e->e.getType()).collect(Collectors.toList());

2 Java批量修改List里面某个属性的方法

方法一:通过流的方式

List<DishFlavor> flavors = dishDto.getFlavors();
flavors = flavors.stream().map((item) -> {
     item.setDishId(dishId);
     return item;
}).collect(Collectors.toList());

方法二:通过forEach

List<DishFlavor> dishList;
dishList.forEach(item -> {
    if (item.getExam_res_start_time().compareTo(oldIBay.getTime_slice_end_time()) >= 0 && item.getExam_res_end_time().compareTo(newTimeSliceEndTimeCur) <= 0) {
        item.setExam_res_statues(DvResourceConstants.EXAM_RES_STATUES.YSC);
} else {
item.setExam_res_statues(item.getExam_res_statues());
item.setExam_res_start_time(newTimeSliceEndTimeCur);
}
});

原文链接:https://blog.csdn.net/weixin_49628243/article/details/124669398

3 关于List的方法removeif()的使用

List<DishFlavor> dishList;
dishList.removeIf(k -> DvResourceConstants.EXAM_RES_STATUES.YSC.equals(k.getExam_res_statues()));

原文链接:https://blog.csdn.net/zhang19age_/article/details/125646734

4 通过Java列表中的属性获取对象的索引

int index = IntStream.range(0, timeSlicePans.size()).filter(i -> timeSlicePans.get(i).getTime_slice_id()
                    .equals(closeTimeSliceId)).findFirst().orElse(-1);

原文链接:https://www.imooc.com/wenda/detail/671687(