一直以来没工夫仔细琢磨菜单树怎么做，只知道递归，现在才有空闲实现一次。

数据结构：

调用部分的代码，浏览器地址为：http://127.0.0.1:8080/admin/resource/menu?userId=23123

buildTree的代码：

public JSONArray buildTree(List
     
       resListAll, List
      
        iteratedList, int parentId) {		JSONArray arr = new JSONArray();		for (Resource resource : resListAll) {			if (iteratedList.contains(resource)) {				continue;			}			if (resource.getParentId() == parentId) {				iteratedList.add(resource);				String text = JSONObject.toJSONString(resource);				JSONObject res = JSONObject.parseObject(text);				arr.add(res);				res.put("children", buildTree(resListAll, iteratedList, resource.getId()));			}		}		return arr;	}
      
     

　　

结果：

{	"resourceTree": [{		"resourceRemark": "",		"resourceContent": "",		"orderNum": 0,		"resourceDescription": "",		"resourceName": "采购管理",		"parentId": 0,		"resourceStatus": "disabled",		"depth": 0,		"resourceUrl": "",		"createTime": 1544149306000,		"children": [{			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "非日常采购",			"parentId": 5,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 23,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "日常采购管理",			"parentId": 5,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 22,			"resourceType": "menu"		}],		"id": 5,		"resourceType": "menu"	}, {		"resourceRemark": "",		"resourceContent": "",		"orderNum": 0,		"resourceDescription": "",		"resourceName": "场地管理",		"parentId": 0,		"resourceStatus": "disabled",		"depth": 0,		"resourceUrl": "",		"createTime": 1544148935000,		"children": [{			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "合作酒店场地管理",			"parentId": 4,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 21,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "会议室场地管理",			"parentId": 4,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 20,			"resourceType": "menu"		}],		"id": 4,		"resourceType": "menu"	}, {		"resourceRemark": "",		"resourceContent": "",		"orderNum": 0,		"resourceDescription": "",		"resourceName": "支出管理",		"parentId": 0,		"resourceStatus": "disabled",		"depth": 0,		"resourceUrl": "",		"createTime": 1544148987000,		"children": [{			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "投标支出管理",			"parentId": 3,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [{				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "星际投标",				"parentId": 19,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [{					"resourceRemark": "",					"resourceContent": "",					"orderNum": 0,					"resourceDescription": "",					"resourceName": "仙女星云投标",					"parentId": 30,					"resourceStatus": "disabled",					"depth": 0,					"resourceUrl": "",					"createTime": 1544443215000,					"children": [],					"id": 33,					"resourceType": "menu"				}, {					"resourceRemark": "",					"resourceContent": "",					"orderNum": 0,					"resourceDescription": "",					"resourceName": "银河系投标",					"parentId": 30,					"resourceStatus": "disabled",					"depth": 0,					"resourceUrl": "",					"createTime": 1544443211000,					"children": [],					"id": 32,					"resourceType": "menu"				}],				"id": 30,				"resourceType": "menu"			}, {				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "国际投标",				"parentId": 19,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [],				"id": 29,				"resourceType": "menu"			}, {				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "国内投标",				"parentId": 19,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [],				"id": 28,				"resourceType": "menu"			}, {				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "省内投标",				"parentId": 19,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [],				"id": 27,				"resourceType": "menu"			}, {				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "市内投标",				"parentId": 19,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [],				"id": 26,				"resourceType": "menu"			}],			"id": 19,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "日常支出管理",			"parentId": 3,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 18,			"resourceType": "menu"		}],		"id": 3,		"resourceType": "menu"	}, {		"resourceRemark": "",		"resourceContent": "",		"orderNum": 0,		"resourceDescription": "",		"resourceName": "考勤管理",		"parentId": 0,		"resourceStatus": "disabled",		"depth": 0,		"resourceUrl": "",		"createTime": 1544148905000,		"children": [{			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "会议考勤管理",			"parentId": 2,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 17,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "日常考勤管理",			"parentId": 2,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 16,			"resourceType": "menu"		}],		"id": 2,		"resourceType": "menu"	}, {		"resourceRemark": "",		"resourceContent": "",		"orderNum": 0,		"resourceDescription": "",		"resourceName": "系统管理",		"parentId": 0,		"resourceStatus": "disabled",		"depth": 0,		"resourceUrl": "",		"createTime": 1544148843000,		"children": [{			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "签到管理",			"parentId": 1,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [{				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "离场签到",				"parentId": 15,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [],				"id": 25,				"resourceType": "menu"			}, {				"resourceRemark": "",				"resourceContent": "",				"orderNum": 0,				"resourceDescription": "",				"resourceName": "进场签到",				"parentId": 15,				"resourceStatus": "disabled",				"depth": 0,				"resourceUrl": "",				"createTime": 1544444261000,				"children": [],				"id": 24,				"resourceType": "menu"			}],			"id": 15,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "页面管理",			"parentId": 1,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 14,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "菜单管理",			"parentId": 1,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 13,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "权限管理",			"parentId": 1,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 12,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "",			"orderNum": 0,			"resourceDescription": "",			"resourceName": "角色管理",			"parentId": 1,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 11,			"resourceType": "menu"		}, {			"resourceRemark": "",			"resourceContent": "/",			"orderNum": 0,			"resourceDescription": "首页页面",			"resourceName": "用户管理",			"parentId": 1,			"resourceStatus": "disabled",			"depth": 0,			"resourceUrl": "",			"createTime": 1544444261000,			"children": [],			"id": 10,			"resourceType": "menu"		}],		"id": 1,		"resourceType": "menu"	}]}