生活日用算法——java 区间重叠判断

百度后看了一些解法,效率虽可能比较高,但相对代码太复杂,不便于阅读与代码交接,自己写了下,方法如下。

方法一:

private void checkOverlap(LinkedList<ActiveExtendDTO> activeExtendDOList) {
        activeExtendDOList.sort(Comparator.comparing(ActiveExtendDTO::getCommodityMinNum));
        Long temp = activeExtendDOList.poll().getCommodityMaxNum();
        for (ActiveExtendDTO activeExtend : activeExtendDOList) {
            if (temp >= activeExtend.getCommodityMinNum()) {
                throw new Exception("区间有重叠");
            }
            temp = activeExtend.getCommodityMaxNum();
        }
    }

方法二(1.8):

private void checkOverlap2(List<ActiveExtendDTO> list) {
        list.stream().sorted(Comparator.comparing(ActiveExtendDTO::getCommodityMinNum))
            .reduce((a, b) -> {
                if (a.getCommodityMaxNum() >= b.getCommodityMinNum()) {
                    throw new Exception("区间有重叠");
                }
                return b;
            });
    }

附ActiveExtendDTO类:

@Data
public class ActiveExtendDTO {

    @ApiModelProperty(value = "最小数量")
    @NotBlank(message = "最小数量不可为空")
    private Long commodityMinNum;

    @ApiModelProperty(value = "最大数量")
    @NotBlank(message = "最大数量不可为空")
    private Long commodityMaxNum;

}