java 递归遍历树形结构

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)); }