Java后端实现-元素拖动排序

@ApiOperation(value = "板块拖动排序")
    @ApiImplicitParams({
            @ApiImplicitParam(name = "plateId1", value = "拖拽体"),
            @ApiImplicitParam(name = "plateId2", value = "参照体"),
            @ApiImplicitParam(name = "type", value = "实现类型1交换位置2挤压位置")
    })
    @PostMapping("plateSort")
    public ServiceResult<Object> plateSort(@RequestParam @NotNull Integer plateId1,
                                           @RequestParam @NotNull Integer plateId2,
                                           @RequestParam @NotNull @Max(2) @Min(1) Integer type) {
        //元素原地拖动
        if (plateId1.equals(plateId2)) {
            return success();
        }

        LambdaQueryWrapper<TiebaPlate> wrapper = new LambdaQueryWrapper<>();
        if (type == 1) {
            //两个元素交换位置
            wrapper
                    .eq(TiebaPlate::getId, plateId1)
                    .or()
                    .eq(TiebaPlate::getId, plateId2);
            List<TiebaPlate> list = tiebaPlateService.list(wrapper);
            int x = list.get(0).getOrderNum();
            int y = list.get(1).getOrderNum();
            list.get(0).setOrderNum(y);
            list.get(1).setOrderNum(x);
            //将collect更新到数据库
            boolean result = tiebaPlateService.updateBatchById(list);
            Assert.isTrue(result, "服务器异常");

            return success();

        } else if (type == 2) {

            if (plateId1 < plateId2) {
                //将plateId1位置拖到plateId2位置下面
                wrapper
                        .between(TiebaPlate::getId, plateId1, plateId2);
                List<TiebaPlate> list = tiebaPlateService.list(wrapper);
                List<TiebaPlate> collect = list.stream().sorted(Comparator.comparingInt(TiebaPlate::getOrderNum)).collect(Collectors.toList());

                //排序标记
                int[] orderNums = collect.stream().mapToInt(TiebaPlate::getOrderNum).toArray();
                //将首位元素挪到末尾
                TiebaPlate first = collect.get(0);
                collect.remove(first);
                collect.add(first);

                //将集合元素和排序标记绑定
                for (int i = 0; i < orderNums.length; i++) {
                    collect.get(i).setOrderNum(orderNums[i]);
                }

                //将collect更新到数据库
                boolean result = tiebaPlateService.updateBatchById(collect);
                Assert.isTrue(result, "服务器异常");

                return success();
            } else {
                //将plateId2位置拖到plateId1前面
                wrapper
                        .between(TiebaPlate::getId, plateId2, plateId1);
                List<TiebaPlate> list = tiebaPlateService.list(wrapper);
                List<TiebaPlate> collect = list.stream().sorted(Comparator.comparingInt(TiebaPlate::getOrderNum)).collect(Collectors.toList());
                //排序标记
                int[] orderNums = collect.stream().mapToInt(TiebaPlate::getOrderNum).toArray();

                //将末尾元素追加到首位
                TiebaPlate last = collect.get(collect.size() - 1);
                collect.remove(last);
                Collections.reverse(collect);
                collect.add(last);
                Collections.reverse(collect);

                //将集合元素和排序标记绑定
                for (int i = 0; i < orderNums.length; i++) {
                    collect.get(i).setOrderNum(orderNums[i]);
                }

                //将collect更新到数据库
                boolean result = tiebaPlateService.updateBatchById(collect);
                Assert.isTrue(result, "服务器异常");

                return success();
            }
        }
        return failure();
    }

思路:如何优雅的实现数据置顶、置尾、交换、拖动排序？ - 简书