Java 递归List返回树状结构

目录

1、此类情况使用场景

2、实现代码

3、数据结果展示：

---

1、此类情况使用场景

     如果直接通过SQL查询，返回给所需树状结构数据，同时按照树的层级进行了排序 如下图所示：

    

2、实现代码

   public static JSONArray treeRecursionDataList(List> treeList, int parentId) {  
       JSONArray childMenu = new JSONArray();  
       for (Object object : treeList) {  
           JSONObject jsonMenu =JSONObject.parseObject(JSON.toJSONString(object));  
           int menuId = jsonMenu.getIntValue("id");  
           int pid = jsonMenu.getIntValue("parentId");  
           if (parentId == pid) {  
               JSONArray c_node = treeRecursionDataList(treeList, menuId);  
               jsonMenu.put("childList", c_node);  
               childMenu.add(jsonMenu);  
           }  
       }  
       return childMenu;  
   } 

    //调用函数
	/**
	 * 获得用户岗位包含的所有分类
	 * @param request
	 * @param 
	 * @return
	 */
	@RequestMapping(value = "/getUserJobRecursionCategoryList")
	@ResponseBody
	public Object getUserJobRecursionCategoryList(HttpServletRequest request,String status){
		PermissionUser user = getCurrentUser(request);
		Long ownerCompany = user.getOwnerCompany();
		Long userJobId=user.getJobId();
		
		Map paramMap = new HashMap();
		paramMap.put("status", status);
		paramMap.put("ownerCompany", ownerCompany);
		paramMap.put("userJobId", userJobId);
		List> userJobCategoryList =null;
		if(userJobId!=null){
			userJobCategoryList =courseCategoryExtendMapper.getUserJobContainAllCategoryList(paramMap);
		}
		JSONArray returnList=treeRecursionDataList(userJobCategoryList, 0);
		return ResultWrapper.create().setRows(returnList).getResultMap();
	}

3、数据结果展示：

{
  "rows": [
    {
      "ownerCompany": 10002, 
      "modifyTime": 1537325781000, 
      "createTime": 1536891501000, 
      "modifyId": 2592, 
      "categoryLevel": "1", 
      "creatorId": 1071, 
      "categoryState": "1", 
      "childList": [
        {
          "ownerCompany": 10002, 
          "modifyTime": 1536891514000, 
          "createTime": 1536891514000, 
          "modifyId": 1071, 
          "categoryLevel": "2", 
          "creatorId": 1071, 
          "categoryState": "1", 
          "childList": [
            {
              "ownerCompany": 10002, 
              "modifyTime": 1537240127000, 
              "createTime": 1536891591000, 
              "modifyId": 1172, 
              "categoryLevel": "3", 
              "creatorId": 1071, 
              "categoryState": "1", 
              "childList": [ ], 
              "id": 152, 
              "categoryName": "职业素养", 
              "parentId": 148, 
              "orgId": 133
            }
          ], 
          "id": 148, 
          "categoryName": "专业理论知识", 
          "parentId": 147, 
          "orgId": 1
        }
      ], 
      "id": 147, 
      "categoryName": "岗位资格性培训1", 
      "parentId": 0, 
      "orgId": 156
    }, 
    {
      "ownerCompany": 10002, 
      "modifyTime": 1535097185000, 
      "createTime": 1534737840000, 
      "modifyId": 1071, 
      "categoryLevel": "1", 
      "creatorId": 1071, 
      "categoryState": "1", 
      "childList": [
        {
          "ownerCompany": 10002, 
          "modifyTime": 1536721891000, 
          "createTime": 1534738691000, 
          "modifyId": 2585, 
          "categoryLevel": "2", 
          "creatorId": 1071, 
          "categoryState": "1", 
          "childList": [
            {
              "ownerCompany": 10002, 
              "modifyTime": 1537240535000, 
              "createTime": 1537240489000, 
              "modifyId": 1172, 
              "categoryLevel": "3", 
              "creatorId": 1172, 
              "categoryState": "1", 
              "childList": [ ], 
              "id": 160, 
              "categoryName": "子分类1", 
              "parentId": 100, 
              "orgId": 133
            }
          ], 
          "id": 100, 
          "categoryName": "工班长培训", 
          "parentId": 82, 
          "orgId": 1
        }, 
        {
          "ownerCompany": 10002, 
          "modifyTime": 1535104574000, 
          "createTime": 1535104547000, 
          "modifyId": 1071, 
          "categoryLevel": "2", 
          "creatorId": 1071, 
          "categoryState": "1", 
          "childList": [
            {
              "ownerCompany": 10002, 
              "modifyTime": 1537240549000, 
              "createTime": 1537240549000, 
              "modifyId": 1172, 
              "categoryLevel": "3", 
              "creatorId": 1172, 
              "categoryState": "1", 
              "childList": [ ], 
              "id": 161, 
              "categoryName": "子分类2", 
              "parentId": 118, 
              "orgId": 133
            }
          ], 
          "id": 118, 
          "categoryName": "特种设备作业培训", 
          "parentId": 82, 
          "orgId": 1
        }
      ], 
      "id": 82, 
      "categoryName": "岗位资格性培训", 
      "parentId": 0, 
      "orgId": 1
    }
  ], 
  "msgInfo": "", 
  "msgCode": "0", 
  "isSuccess": "true"
}

记录一下可参考文章：https://www.jb51.net/article/125076.htm