谷粒商场P150优化三级分类获取

改进

    @Override     public Map<String, List<Catelog2Vo>> getCatalogJson() { 
                ///将数据库的多次查询变为一次         List<CategoryEntity> selectList = baseMapper.selectList(null);           // 查询所有一级分类         List<CategoryEntity> level1 = getParent_cid(selectList,0L);          Map<String, List<Catelog2Vo>> catalogJson = level1.stream().collect(Collectors.toMap(k -> k.getCatId().toString(), v -> { 
                    // 拿到每一级分类 然后查询他们的二级分类             List<CategoryEntity> level2 = getParent_cid(selectList,v.getCatId());             List<Catelog2Vo> catelog2Vos = null;             if (level2 != ) { 
         catelog2Vos = level2.stream().map(l2 -> { 
         Catelog2Vo catelog2Vo = new Catelog2Vo(v.getCatId().toString(),null , l2.getCatId().toString(), l2.getName()); // 找当前二级分类的三级分类 List<CategoryEntity> level3 = getParent_cid(selectList,l2.getCatId()); // 三级分类有数据的情况下 if (level3 != null) { 
         List<Catelog2Vo.Catelog3Vo> catelog3Vos = level3.stream().map((l3) -> { 
         Catelog2Vo.Catelog3Vo catelog3Vo = new Catelog2Vo.Catelog3Vo(l2.getCatId().toString(),l3.getCatId().toString(),l3.getName()); return catelog3Vo; }).collect(Collectors.toList()); catelog2Vo.setCatalog3List(catelog3Vos); } return catelog2Vo; }).collect(Collectors.toList()); } return catelog2Vos; })); return catalogJson; } private List<CategoryEntity> getParent_cid( List<CategoryEntity> selectList,Long parent_cid) { 
         List<CategoryEntity> collect = selectList.stream().filter(item -> item.getParentCid() == parent_cid).collect(Collectors.toList()); return collect; }