Java实现多级菜单(递归实现)

Java实现多级菜单

菜单管理数据库设计

pgsql表

CREATE TABLE "ads"."sys_menu_permission" (
"menu_id" int4 DEFAULT nextval('"ads".sys_menu_permission_menu_id_seq'::regclass) NOT NULL,
"menu_pid" int4 DEFAULT 0,
"menu_name" varchar(100) COLLATE "default",
"menu_type" varchar(20) COLLATE "default",
"url" varchar(100) COLLATE "default",
"active" varchar(1) COLLATE "default" DEFAULT 1,
"visible" varchar(1) COLLATE "default" DEFAULT 1,
"sort" int4 DEFAULT 0,
"level" int4,
"icon" varchar(100) COLLATE "default",
"created_at" timestamp DEFAULT now(),
CONSTRAINT "sys_menu_permission_pkey" PRIMARY KEY ("menu_id")
)
WITH (OIDS=FALSE)
;

菜单管理实体类

@Data
public class SysMenuPermissionEntityParent extends BaseEntity { 
	private static final long serialVersionUID = 1L;
	
	/** * ID */
	private Integer menuId;
	/** * 菜单父ID */
	private Integer menuPid;
	/** * 菜单名称 */
	private String menuName;
	/** * 菜单类型(menu, permission) */
	private String menuType;

	List<SysMenuPermissionEntity> children;
	
	/** * 路由地址 */
	private String url;
	/** * 是否可用(1:可用;0:不可用) */
	private String active;
	/** * 是否可见(1:可见;0:不可见) */
	private String visible;
	/** * 组内排序 */
	private Integer sort;
	/** * 菜单层级 */
	private Integer level;
	/** * 矢量图标 */
	private String icon;
	/** * 创建时间 */
	private Date createdAt;
}

Controller 层

/** * 查询菜单列表(递归查询) * @return */
@ApiOperation("递归查询菜单列表")
@GetMapping("/findMenuList")
@IgnoreServiceAuth
public Map<String, Object> findMenuList() { 
	return sysMenuPermissionService.findMenuList();
}

Service 层

@Override
public Map<String, Object> findMenuList() { 
    Map<String, Object> data = new HashMap<>();
    try {  //查询所有菜单
        List<SysMenuPermissionEntity> allMenu = sysMenuPermissionMapper.queryList();
        //根节点集合
        List<SysMenuPermissionEntity> rootMenu = new ArrayList<>();
        for (SysMenuPermissionEntity entity : allMenu) { 
            if (entity.getMenuPid() == 0) {  //父节点是0的，为根节点。
                rootMenu.add(entity);
            }
        }
        /* 根据Menu类的order排序 */
        //Collections.sort(rootMenu, order());
        //为根菜单设置子菜单，getClild是递归调用的
        for (SysMenuPermissionEntity entity : rootMenu) { 
            /* 获取根节点下的所有子节点 使用getChild方法*/
            List<SysMenuPermissionEntity> childList = getChild(entity.getMenuId().toString(), allMenu);
            entity.setChildren(childList);//给根节点设置子节点
        }
        /** * 输出构建好的菜单数据。 */
        data.put("code", "0");
        data.put("msg", "ok");
        data.put("result", rootMenu);
        return data;
    } catch (Exception e) { 
        data.put("code", "-1");
        data.put("result", new ArrayList());
        return data;
    }
}

/** * 获取子节点 * * @param id 父节点id * @param allMenu 所有菜单列表 * @return 每个根节点下，所有子菜单列表 */
public List<SysMenuPermissionEntity> getChild(String id, List<SysMenuPermissionEntity> allMenu) { 
    //子菜单
    List<SysMenuPermissionEntity> childList = new ArrayList<>();
    for (SysMenuPermissionEntity entity : allMenu) { 
        // 遍历所有节点，将所有菜单的父id与传过来的根节点的id比较
        //相等说明：为该根节点的子节点。
        if (entity.getMenuPid().toString().equals(id)) { 
            childList.add(entity);
        }
    }
    //递归
    for (SysMenuPermissionEntity entity : childList) { 
        entity.setChildren(getChild(entity.getMenuId().toString(), allMenu));
    }
    //Collections.sort(childList,order()); //排序
    //如果节点下没有子节点，返回一个空List（递归退出）
    if (childList.size() == 0) { 
        return new ArrayList<>();
    }
    return childList;
}

Dao 层

<select id="queryList" resultMap="ResultMap">
	select
	<include refid="Column_List" />
	from ads.sys_menu_permission
	<include refid="Example_Where_Clause" />
	<if test="orderBy != null and orderBy != ''">
		order by ${ orderBy}
	</if>
</select>

模拟表数据

返回给前端的JSON数据

{ 
  "msg": "ok",
  "result": [
    { 
      "menuId": 1,
      "menuPid": 0,
      "menuName": "test menu",
      "menuType": "menu",
      "active": "1",
      "visible": "1",
      "sort": 0,
      "level": 1,
      "createdAt": "2020-11-03 00:00:00",
      "children": [
        { 
          "menuId": 6,
          "menuPid": 1,
          "menuName": "ggg",
          "children": [
            { 
              "menuId": 12,
              "menuPid": 6,
              "menuName": "sads2c",
              "menuType": "22r32sac",
              "url": "sfafa2s",
              "active": "1",
              "visible": "1",
              "sort": 0,
              "createdAt": "2020-11-18 18:05:14",
              "children": []
            }
          ]
        },
        { 
          "menuId": 3,
          "menuPid": 1,
          "menuName": "string",
          "menuType": "string",
          "url": "string",
          "active": "1",
          "visible": "s",
          "sort": 0,
          "level": 0,
          "createdAt": "2020-11-16 17:00:00",
          "children": [
            { 
              "menuId": 9,
              "menuPid": 3,
              "menuName": "dsdsaf",
              "menuType": "sadfas",
              "url": "sfas",
              "active": "1",
              "visible": "1",
              "sort": 0,
              "createdAt": "2020-11-18 18:04:42",
              "children": []
            },
            { 
              "menuId": 10,
              "menuPid": 3,
              "menuName": "dsaf2sdsc",
              "menuType": "fasdf",
              "url": "sdfasd",
              "active": "1",
              "visible": "1",
              "sort": 0,
              "createdAt": "2020-11-18 18:04:53",
              "children": []
            }
          ]
        },
        { 
          "menuId": 4,
          "menuPid": 1,
          "menuName": "hhh",
          "menuType": "hhh",
          "url": "hhh",
          "active": "1",
          "visible": "0",
          "sort": 0,
          "level": 0,
          "icon": "hhh",
          "createdAt": "2020-11-16 17:00:00",
          "children": [
            { 
              "menuId": 11,
              "menuPid": 4,
              "menuName": "2dsaf",
              "menuType": "asf2dhg",
              "url": "hgfgj",
              "active": "1",
              "visible": "1",
              "sort": 0,
              "createdAt": "2020-11-18 18:05:02",
              "children": []
            }
          ]
        }
      ]
    },
    { 
      "menuId": 2,
      "menuPid": 0,
      "menuName": "test2",
      "menuType": "menu",
      "active": "1",
      "visible": "1",
      "sort": 0,
      "createdAt": "2020-11-03 15:31:20",
      "children": [
        { 
          "menuId": 7,
          "menuPid": 2,
          "menuName": "dfa",
          "menuType": "dfa",
          "url": "fadfa",
          "active": "1",
          "visible": "1",
          "sort": 0,
          "createdAt": "2020-11-18 17:43:11",
          "children": []
        },
        { 
          "menuId": 8,
          "menuPid": 2,
          "menuName": "2333",
          "menuType": "safa23",
          "url": "dfas3c",
          "active": "1",
          "visible": "1",
          "sort": 0,
          "icon": "",
          "createdAt": "2020-11-18 17:43:31",
          "children": []
        },
        { 
          "menuId": 5,
          "menuPid": 2,
          "menuName": "sfas",
          "menuType": "23",
          "url": "232fdsfa",
          "active": "1",
          "visible": "1",
          "sort": 0,
          "createdAt": "2020-11-18 17:46:11",
          "children": []
        }
      ]
    }
  ],
  "code": "0"
}