赞
踩
以前在java中构建菜单、区划等都是使用递归或是数据库。
数据库如pg、mysql等原生不支持tree结构,递归不是很好理解,同时代码太长。所以考虑使用java1.8以后支持的lambda操作一波
PS:数据库我使用了mybatis-plus,所以查数据的写法简化了
//查找所有菜单,正序排序 List<MenuEntity> list = this.list(Wrappers.lambdaQuery(MenuEntity.class) .eq(MenuEntity::getHide, BoolStateEnum.FALSE.getCode()) .orderByAsc(MenuEntity::getSort)); //找寻下级菜单,利用.map来保证引用地址相同 list.stream() .map(ele -> { ele.setChildren(this.fromTree(ele, list)); return ele; }) .collect(Collectors.toList()); //过滤出最上级的菜单 return list.stream() .filter(ele -> ele.getParentId() == null) .collect(Collectors.toList());
/**
* 找寻指定菜单的下级菜单
*
* @param menuEntity 当前菜单
* @param list 所有的菜单list
* @return 下级菜单
*/
private List<MenuEntity> fromTree(MenuEntity menuEntity, List<MenuEntity> list) {
return list.stream()
.filter(ele -> menuEntity.getId().equals(ele.getParentId()))
.collect(Collectors.toList());
}
public class MenuEntity { @ApiModelProperty(value = "ID") @TableId private Long id; @ApiModelProperty(value = "创建时间") private LocalDateTime createTime; @ApiModelProperty(value = "创建人ID") private String createUserId; @ApiModelProperty(value = "修改时间") private LocalDateTime updateTime; @ApiModelProperty(value = "修改人ID") private String updateUserId; @ApiModelProperty(value = "节点名") private String name; @ApiModelProperty(value = "所有上级节点id列表 为空时表示最顶层") private Long parentId; @ApiModelProperty(value = "菜单类型 0=节点 1=菜单 2=按钮") private int menuType; @ApiModelProperty(value = "图标") private String icon; @ApiModelProperty(value = "url") private String url; @ApiModelProperty(value = "hash路由") private String hash; @ApiModelProperty(value = "是否隐藏 0=不隐藏 1=隐藏") private int hide; @ApiModelProperty(value = "排序,从小到大正向排序") private int sort; @ApiModelProperty(value = "下级菜单集合") @TableField(exist = false) private List<MenuEntity> children; }
Copyright © 2003-2013 www.wpsshop.cn 版权所有,并保留所有权利。