java 高效遞歸查詢樹 find_in_set 處理遞歸樹

建表語句

DROP TABLE IF EXISTS `sys_dept`;
CREATE TABLE `sys_dept` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '部門id',
  `parent_id` bigint(20) DEFAULT '0' COMMENT '父部門id',
  `ancestors` varchar(256) DEFAULT '' COMMENT '祖級列表',
  `dept_name` varchar(64) DEFAULT '' COMMENT '部門名稱',
  `order_num` int(4) DEFAULT '0' COMMENT '顯示順序',
  `status` tinyint(1) DEFAULT '0' COMMENT '部門狀態（0正常 1停用）',
  `create_time` datetime DEFAULT NULL COMMENT '創建時間',
  `create_user_id` bigint(20) DEFAULT NULL COMMENT '創建人id',
  `create_user_name` varchar(64) DEFAULT NULL COMMENT '創建人姓名',
  `update_time` datetime DEFAULT NULL COMMENT '修改時間',
  `update_user_id` bigint(20) DEFAULT NULL COMMENT '修改人id',
  `update_user_name` varchar(64) DEFAULT NULL COMMENT '修改人姓名',
  PRIMARY KEY (`id`) USING BTREE,
  UNIQUE KEY `uk_dept_name` (`parent_id`,`dept_name`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8 COMMENT='部門表';

-- ----------------------------
-- Records of sys_dept
-- ----------------------------
BEGIN;
INSERT INTO `sys_dept` VALUES (1, 0, '0', 'XX科技', 0, 0, '2021-10-09 10:31:47', 1, '系統管理員', NULL, NULL, NULL);
INSERT INTO `sys_dept` VALUES (2, 1, '0,1', '商務部', 3, 0, '2021-12-06 15:33:20', 1, '系統管理員', '2021-12-06 15:58:30', 1234, '管理');
INSERT INTO `sys_dept` VALUES (3, 1, '0,1', 'XX關務部', 4, 0, '2021-12-06 15:37:01', 1, '系統管理員', '2021-12-06 15:40:15', 1, '系統管理員');
INSERT INTO `sys_dept` VALUES (4, 1, '0,1', 'XX貨主', 6, 0, '2021-12-06 15:38:34', 1, '系統管理員', '2021-12-06 17:17:27', 1, '系統管理員');
INSERT INTO `sys_dept` VALUES (5, 1, '0,1', '技術部', 1, 0, '2021-12-06 15:39:22', 1, '系統管理員', '2021-12-06 15:57:48', 1234, '管理');
INSERT INTO `sys_dept` VALUES (6, 4, '0,1,4', '貨主-A', 1, 0, '2021-12-06 16:15:26', 1234, '小A', '2021-12-06 17:16:33', 1, '系統管理員');
INSERT INTO `sys_dept` VALUES (7, 4, '0,1,4', '貨主-B', 2, 0, '2021-12-06 16:15:39', 1234, '小A', '2021-12-06 17:17:37', 1, '系統管理員');
INSERT INTO `sys_dept` VALUES (8, 6, '0,1,4,6', '1', 11, 0, '2022-03-16 10:27:28', 1, '系統管理員', '2022-03-16 10:27:37', 1, '系統管理員');
INSERT INTO `sys_dept` VALUES (9, 8, '0,1,4,6,8', '111111', 0, 0, '2022-03-16 10:27:45', 1, '系統管理員', NULL, NULL, NULL);
COMMIT;

新增

@Data
@ApiModel(value = "部門編輯對象", description = "部門編輯請求對象")
public class DeptEditRequest {
    @ApiModelProperty(value = "主鍵id", example = "-1")
    @DecimalMin(value = "1", message = "角色id最小爲1")
    private Long id;

    @ApiModelProperty(value = "父部門id", example = "-1")
    @NotNull(message = "上級部門" + HibernateConstant.NOT_NULL)
    @JsonProperty("parent_id")
    private Long parentId;

    @ApiModelProperty(value = "部門名稱", example = "IT部")
    @NotBlank(message = "部門名稱" + HibernateConstant.NOT_NULL)
    @JsonProperty("dept_name")
    private String deptName;

    @ApiModelProperty(value = "顯示順序", example = "0")
    @NotNull(message = "顯示" + HibernateConstant.NOT_NULL)
    @JsonProperty("order_num")
    private Integer orderNum;

    @ApiModelProperty(value = "部門狀態（0正常 1停用）", example = "0")
    @Min(value = 0, message = "部門狀態（0正常 1停用）")
    @Max(value = 1, message = "部門狀態（0正常 1停用）")
    private byte status;
}

    @ApiOperation("部門添加")
    @PostMapping("add")
    public JsonData add(
            @RequestBody DeptAddRequest request
    ) {
        return deptService.add(request);
    }

    @Override
    public JsonData add(DeptAddRequest request) {
        DeptEditRequest deptEditRequest = new DeptEditRequest();
        BeanUtils.copyProperties(request, deptEditRequest);
        //同級部門下，部門名稱重複
        checkDeptNameUnique(deptEditRequest);
        DeptDO deptDO = new DeptDO();
        deptDO.setDeptName(request.getDeptName());
        deptDO.setParentId(request.getParentId());
        deptDO.setStatus(request.getStatus());
        deptDO.setOrderNum(request.getOrderNum());
        deptDO.setCreateTime(CommonUtil.getCurrentDate());
        deptDO.setCreateUserId(CommonUtil.getCurrentUserId());
        deptDO.setCreateUserName(CommonUtil.getCurrentUserName());
        //檢查上級部門狀態
        checkParentDeptState(deptDO);
        int rows = deptMapper.add(deptDO);
        if (rows > 0) {
            log.info("部門添加，rows:{}，添加成功:{}", rows, deptDO);
            return JsonData.buildAddSuccess();
        }
        return JsonData.buildError("添加失敗");
    }


    /**
     * 部門名稱唯一值
     *
     * @param request
     */
    private void checkDeptNameUnique(DeptEditRequest request) {
        List<DeptDO> deptList = deptMapper.selectList(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getDeptName, request.getDeptName())
                        .eq(DeptDO::getParentId, request.getParentId())
        );
        for (DeptDO deptDO : deptList) {
            if (deptDO.getId() != request.getId()) {
                throw new BizException(500, "部門已存在");
            }
        }
    }


    /**
     * 檢查上級部門狀態
     *
     * @param dept 部門對象
     */
    private void checkParentDeptState(DeptDO dept) {
        DeptDO deptDO = deptMapper.selectOne(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getId, dept.getParentId())
        );
        if (deptDO == null) {
            throw new BizException(500, "上級部門不存在");
        }
        if (1 == deptDO.getStatus()) {
            throw new BizException(500, "上級部門已停用，不允許新增");
        }
        dept.setAncestors(deptDO.getAncestors() + "," + dept.getParentId());
    }

編輯

@Data
@ApiModel(value = "部門編輯對象", description = "部門編輯請求對象")
public class DeptEditRequest {
    @ApiModelProperty(value = "主鍵id", example = "-1")
    @DecimalMin(value = "1", message = "角色id最小爲1")
    private Long id;

    @ApiModelProperty(value = "父部門id", example = "-1")
    @NotNull(message = "上級部門" + HibernateConstant.NOT_NULL)
    @JsonProperty("parent_id")
    private Long parentId;

    @ApiModelProperty(value = "部門名稱", example = "IT部")
    @NotBlank(message = "部門名稱" + HibernateConstant.NOT_NULL)
    @JsonProperty("dept_name")
    private String deptName;

    @ApiModelProperty(value = "顯示順序", example = "0")
    @NotNull(message = "顯示" + HibernateConstant.NOT_NULL)
    @JsonProperty("order_num")
    private Integer orderNum;

    @ApiModelProperty(value = "部門狀態（0正常 1停用）", example = "0")
    @Min(value = 0, message = "部門狀態（0正常 1停用）")
    @Max(value = 1, message = "部門狀態（0正常 1停用）")
    private byte status;
}

    @ApiOperation("部門修改")
    @PostMapping("edit")
    public JsonData edit(
            @RequestBody DeptEditRequest request
    ) {
        if (request.getId() == 1) {
            throw new BizException(500, "不允許操作系統默認部門");
        }
        return deptService.edit(request);
    }

    @Override
    @Transactional
    public JsonData edit(DeptEditRequest request) {
        DeptDO deptDO = new DeptDO();
        BeanUtils.copyProperties(request, deptDO);
        //同級部門下，部門名稱重複
        checkDeptNameUnique(request);
        //檢查上級部門狀態
        checkParentDeptState(deptDO);
        //上級部門不能是自己
        checkParentDept(request);
        //父級對象
        DeptDO parentDept = deptMapper.selectOne(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getId, deptDO.getParentId())
        );
        if (parentDept == null) {
            throw new BizException(500, "上級部門不存在");
        }
        DeptDO oldDept = deptMapper.selectOne(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getId, deptDO.getId())
        );
        if (oldDept == null) {
            throw new BizException(500, "記錄不存在，請稍後重試");
        }
        String newAncestors = parentDept.getAncestors() + "," + parentDept.getId();
        String oldAncestors = oldDept.getAncestors();
        deptDO.setAncestors(newAncestors);
        byte oldState = oldDept.getStatus();
        int rows = deptMapper.updateById(deptDO);
        if (rows > 0) {
            log.info("部門修改，rows:{},修改成功:{}", rows, deptDO);
            //遞歸處理子部門狀態
            if (oldState != deptDO.getStatus()) {
                updateChildDeptState(deptDO, newAncestors, oldAncestors);
            }
            return JsonData.buildEditSuccess();
        }
        return JsonData.buildError("修改失敗");
    }


    /**
     * 部門名稱唯一值
     *
     * @param request
     */
    private void checkDeptNameUnique(DeptEditRequest request) {
        List<DeptDO> deptList = deptMapper.selectList(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getDeptName, request.getDeptName())
                        .eq(DeptDO::getParentId, request.getParentId())
        );
        for (DeptDO deptDO : deptList) {
            if (deptDO.getId() != request.getId()) {
                throw new BizException(500, "部門已存在");
            }
        }
    }


    /**
     * 檢查上級部門狀態
     *
     * @param dept 部門對象
     */
    private void checkParentDeptState(DeptDO dept) {
        DeptDO deptDO = deptMapper.selectOne(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getId, dept.getParentId())
        );
        if (deptDO == null) {
            throw new BizException(500, "上級部門不存在");
        }
        if (1 == deptDO.getStatus()) {
            throw new BizException(500, "上級部門已停用，不允許新增");
        }
        dept.setAncestors(deptDO.getAncestors() + "," + dept.getParentId());
    }

    /**
     * 上級部門不能是自己
     *
     * @param request
     */
    private void checkParentDept(DeptEditRequest request) {
        if (request.getId().equals(request.getParentId())) {
            throw new BizException(500, "上級部門不能是自己");
        }
    }

    /**
     * 處理子部門狀態
     *
     * @param deptDO       部門對象
     * @param newAncestors 新的父ID集合
     * @param oldAncestors 舊的父ID集合
     */
    private void updateChildDeptState(DeptDO deptDO, String newAncestors, String oldAncestors) {
        deptMapper.batchUpdateChildDeptState(deptDO.getId(), deptDO.getStatus());
        //找所有子部門
        List<DeptDO> deptList = deptMapper.selectChildrenDeptById(deptDO.getId());
        for (DeptDO dpt : deptList) {
            dpt.setAncestors(dpt.getAncestors().replaceFirst(oldAncestors, newAncestors));
            deptMapper.updateById(dpt);
        }
    }

    /**
     * 批量更新子部門狀態
     *
     * @param id    部門id
     * @param state 狀態
     * @return
     */
    int batchUpdateChildDeptState(
            @Param("id") Long id,
            @Param("state") Byte state
    );

    <!-- 批量更新子部門狀態 -->
    <update id="batchUpdateChildDeptState">
        UPDATE
            sys_dept
        SET
            `status`=#{state}
        WHERE ancestors LIKE CONCAT('%',#{id},'%')
    </update>


    /**
     * 根據id找所有子部門
     *
     * @param id
     * @return
     */
    List<DeptDO> selectChildrenDeptById(@Param("id") Long id);

    <!-- 根據id找所有子部門 -->
    <select id="selectChildrenDeptById" resultMap="BaseResultMap">
        SELECT
            id,
            parent_id,
            ancestors,
            dept_name,
            order_num,
            `status`,
            create_time,
            create_user_id,
            create_user_name,
            update_time,
            update_user_id,
            update_user_name
        FROM
            sys_dept
        WHERE
            FIND_IN_SET(#{id},ancestors)
    </select>

刪除

    @ApiOperation("部門刪除")
    @GetMapping("remove")
    public JsonData remove(
            @ApiParam(value = "部門id", required = true) @RequestParam(value = "id", required = true) Long id
    ) {
        if (id == 1) {
            throw new BizException(500, "不允許操作系統默認部門");
        }
        return deptService.remove(id);
    }

    @Override
    public JsonData remove(Long id) {
        int rows = deptMapper.deleteById(id);
        if (rows > 0) {
            log.info("部門刪除，rows:{},刪除成功:{}", rows, id);
            //遞歸刪除子部門
            removeChildDept(id);
            return JsonData.buildRemoveSuccess();
        }
        return JsonData.buildError("部門刪除失敗");
    }

    /**
     * 刪除子部門
     *
     * @param parentId
     */
    private void removeChildDept(Long parentId) {
        List<DeptDO> deptList = deptMapper.selectList(
                new LambdaQueryWrapper<DeptDO>()
                        .eq(DeptDO::getParentId, parentId)
        );
        for (DeptDO deptDO : deptList) {
            deptMapper.deleteById(deptDO.getId());
            removeChildDept(deptDO.getId());
        }
    }

遞歸樹

@Data
@ApiModel(value = "DeptTreeVo對象", description = "部門樹對象信息")
public class DeptTreeVo {
    @ApiModelProperty("節點id")
    @JsonSerialize(using = ToStringSerializer.class)
    private Long id;

    @ApiModelProperty("節點名稱")
    private String label;

    @ApiModelProperty("子節點")
    @JsonInclude(JsonInclude.Include.NON_EMPTY)
    private List<DeptTreeVo> children;
}

    @ApiOperation("部門樹")
    @GetMapping("deptTree")
    public JsonData<List<DeptTreeVo>> deptTree() {
        return deptService.deptTree();
    }

    private static final ThreadPoolExecutor THREAD_POOL_EXECUTOR = new ThreadPoolExecutor(
            APS * 2,
            APS * 4,
            KEEP_ALIVE_TIME,
            TimeUnit.SECONDS,
            new LinkedBlockingDeque<>(256),
            new ThreadFactoryBuilder().setNameFormat("部門-pool-%d").build(),
            new ThreadPoolExecutor.CallerRunsPolicy()
    );

    @Override
    public JsonData<List<DeptTreeVo>> deptTree() {
        LambdaQueryWrapper<DeptDO> wrapper = new LambdaQueryWrapper<DeptDO>();
        wrapper.orderByAsc(DeptDO::getParentId, DeptDO::getOrderNum);
        List<DeptDO> deptList = deptMapper.selectList(wrapper);
        return buildDeptTree(deptList);
    }



    /**
     * 構建前端需要構建樹結構
     *
     * @param deptList 部門集合
     * @return
     */
    private JsonData<List<DeptTreeVo>> buildDeptTree(List<DeptDO> deptList) {
        List<DeptTreeVo> deptTreeList = new ArrayList<>();
        List<DeptDO> rootDeptList = deptList.stream().filter(obj -> 1 == obj.getId()).collect(Collectors.toList());
        CountDownLatch latch = new CountDownLatch(rootDeptList.size());
        for (DeptDO deptDO : rootDeptList) {
            THREAD_POOL_EXECUTOR.execute(() -> {
                DeptTreeVo vo = new DeptTreeVo();
                vo.setId(deptDO.getId());
                vo.setLabel(deptDO.getDeptName());
                buildChildrentDeptTree(deptList, deptDO.getId(), vo);
                deptTreeList.add(vo);
                latch.countDown();
            });
        }
        try {
            latch.await();
        } catch (InterruptedException e) {
            log.error("構建部門樹結構線程報錯:{}", e);
        }
        return JsonData.buildSuccess(deptTreeList);
    }


    /**
     * 構建子部門樹
     *
     * @param deptList 部門集合
     * @param parentId 父ID
     * @param vo       部門樹
     */
    private void buildChildrentDeptTree(List<DeptDO> deptList, Long parentId, DeptTreeVo vo) {
        List<DeptDO> childList = deptList.stream().filter(obj -> parentId == obj.getParentId()).collect(Collectors.toList());
        List<DeptTreeVo> childDeptTreeList = new ArrayList<>();
        for (DeptDO deptDO : childList) {
            DeptTreeVo dtv = new DeptTreeVo();
            dtv.setId(deptDO.getId());
            dtv.setLabel(deptDO.getDeptName());
            buildChildrentDeptTree(deptList, deptDO.getId(), dtv);
            childDeptTreeList.add(dtv);
        }
        vo.setChildren(childDeptTreeList);
    }


@Data
@TableName("sys_dept")
@ApiModel(value = "SysDeptDO對象", description = "部門表")
public class DeptDO implements Serializable {

    private static final long serialVersionUID = 1L;

    @ApiModelProperty(value = "部門id")
    @TableId(value = "id", type = IdType.AUTO)
    private Long id;

    @ApiModelProperty(value = "父部門id")
    private Long parentId;

    @ApiModelProperty(value = "祖級列表")
    private String ancestors;

    @ApiModelProperty(value = "部門名稱")
    private String deptName;

    @ApiModelProperty(value = "顯示順序")
    private Integer orderNum;

    @ApiModelProperty(value = "部門狀態（0正常 1停用）")
    private byte status;

    @ApiModelProperty(value = "創建時間")
    @TableField(value = "create_time", fill = FieldFill.INSERT)
    private Date createTime;

    @ApiModelProperty(value = "創建人id")
    @TableField(value = "create_user_id", fill = FieldFill.INSERT)
    private Long createUserId;

    @ApiModelProperty(value = "創建人姓名")
    @TableField(value = "create_user_name", fill = FieldFill.INSERT)
    private String createUserName;

    @ApiModelProperty(value = "修改時間")
    @TableField(value = "update_time", fill = FieldFill.UPDATE)
    private Date updateTime;

    @ApiModelProperty(value = "修改人id")
    @TableField(value = "update_user_id", fill = FieldFill.UPDATE)
    private Long updateUserId;

    @ApiModelProperty(value = "修改人姓名")
    @TableField(value = "update_user_name", fill = FieldFill.UPDATE)
    private String updateUserName;
}