java 递归遍历树形结构

川长思鸟来 2022-06-13 10:58 494阅读 0赞

好记性不如烂笔头，记录下。
    
    //菜单树形结构  
       public JSONArray treeMenuList(JSONArray menuList, int parentId) {  
           JSONArray childMenu = new JSONArray();  
           for (Object object : menuList) {  
               JSONObject jsonMenu = JSONObject.fromObject(object);  
               int menuId = jsonMenu.getInt("id");  
               int pid = jsonMenu.getInt("parentId");  
               if (parentId == pid) {  
                   JSONArray c_node = treeMenuList(menuList, menuId);  
                   jsonMenu.put("childNode", c_node);  
                   childMenu.add(jsonMenu);  
               }  
           }  
           return childMenu;  
       }  
    
    public static void main(String args[]) {  
           MenuCacheService menuCacheService = new MenuCacheService();  
           JSONArray jsonArray = new JSONArray();  
           Menu menu1 = new Menu();  
           menu1.setId(1l);  
           menu1.setParentId(0);  
           menu1.setLevel(0);  
           Menu menu2 = new Menu();  
           menu2.setId(2l);  
           menu2.setParentId(0);  
           menu2.setLevel(0);  
           Menu menu3 = new Menu();  
           menu3.setId(3l);  
           menu3.setParentId(2);  
           menu3.setLevel(1);  
           Menu menu4 = new Menu();  
           menu4.setId(4l);  
           menu4.setParentId(2);  
           menu4.setLevel(1);  
           Menu menu5 = new Menu();  
           menu5.setId(5l);  
           menu5.setParentId(4);  
           menu5.setLevel(2);  
           Menu menu6 = new Menu();  
           menu6.setId(6l);  
           menu6.setParentId(1);  
           menu6.setLevel(1);  
    
           jsonArray.add(menu1);  
           jsonArray.add(menu2);  
           jsonArray.add(menu3);  
           jsonArray.add(menu4);  
           jsonArray.add(menu5);  
           jsonArray.add(menu6);  
    
           System.out.print(menuCacheService.treeMenuList(jsonArray,0));  
       }