SpringBoot + MyBatis Plus 递归获取树形菜单信息列表(附源码)

package cn.service.impl; import cn.entity.CategoryEntity; import cn.mapper.CategoryMapper; import cn.service.CategoryService; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import org.springframework.stereotype.Service; import java.util.List; import java.util.stream.Collectors; /** * @author yanglinfengkk * @version 1.0 * @description 商品三级分类业务接口实现类 * @date 2022-12-12 */ @Service public class CategoryServiceImpl extends ServiceImpl<CategoryMapper, CategoryEntity> implements CategoryService { /** * 获取三级分类列表 * * @return 树形菜单列表 */ @Override public List<CategoryEntity> listWithTree() { //1、查询出所有分类 List<CategoryEntity> entities = super.baseMapper.selectList(null); //组装成父子的树形结构 //2.1)、找到所有一级分类 List<CategoryEntity> levelMenus = entities.stream() .filter(e -> e.getParentId() == 0) .map((menu) -> { menu.setChildren(getChildrens(menu, entities)); return menu; }) .sorted((menu, menu2) -> { return (menu.getSort() == null ? 0 : menu.getSort()) - (menu2.getSort() == null ? 0 : menu2.getSort()); }) .collect(Collectors.toList()); return levelMenus; } /** * 递归查找所有菜单的子菜单 * * @param root 商品三级分类对象 * @param all 商品三级分类对象父列表 * @return */ private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all) { return all.stream().filter(categoryEntity -> { return categoryEntity.getParentId().equals(root.getCatId()); }).map(categoryEntity -> { //1、找到子菜单(递归) categoryEntity.setChildren(getChildrens(categoryEntity, all)); return categoryEntity; }).sorted((menu, menu2) -> { //2、菜单的排序 return (menu.getSort() == null ? 0 : menu.getSort()) - (menu2.getSort() == null ? 0 : menu2.getSort()); }).collect(Collectors.toList()); } }