1.在DAO中的實現代碼：

public List<TreeResult> parseMenuTree(List<TreeResult> list){List<TreeResult> result = new ArrayList<>();//1.獲取第一個節點for (TreeResult menu:list) {if(null == menu.getParentId()){result.add(menu);}}//2.獲取遞歸子節點for (TreeResult parent:result) {parent = menuChild(parent,list);}return result; }public TreeResult menuChild(TreeResult parent,List<TreeResult> list){for (TreeResult menu:list) {if(Objects.equals(parent.getId(),menu.getParentId())){parent.getChildren().add(menu);menu = menuChild(menu,list);}}return parent; }

2.在Controller中的實現代碼：

@ApiOperation(value = "動態菜單", httpMethod = "POST", produces = "application/json;charset=UTF-8") @ApiImplicitParam(value = "token", name = "token", dataType = "String", paramType = "header") @PostMapping("/api/menu/tree") public Result menuTree(HttpServletRequest request) {Map<String, Object> map = new HashMap<>();try {User user = userService.getDao().findById(Integer.valueOf(tokenService.valid(request.getHeader("token"))));if (user == null) {return Result.fail(902, "用戶登錄失效，請重新登錄");}if (Enums.UserType.Driver == user.getType()) {return Result.fail(903, "該用戶沒有權限");}if (Enums.UserType.Passenger == user.getType()) {return Result.fail(903, "該用戶沒有權限");}//根據用戶對應的角色獲取角色對應的菜單idList<Integer> integers = roleAndMenuService.getDao().findByRoleId(user.getRoles());List<String> list = integers.stream().map(x -> x + "").collect(Collectors.toList());String menus = String.join(",", list);//根據菜單id獲取對應的菜單List<TreeResult> tree = menuService.getDao().findTree(menus);//將菜單列表轉成樹結構List<TreeResult> treeResults = menuService.getDao().parseMenuTree(tree);map.put("list", treeResults);return Result.ok(map);} catch (Exception e) {e.printStackTrace();return Result.fail(901, e.getMessage());} }

3.TreeResult實體類：

@Getter @Setter public class TreeResult {private Integer id;private String icon;private String menuName;private String menuType;private String menuUrl;private Integer parentId;private List<TreeResult> children = new ArrayList<TreeResult>();}

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