三級分類

CategoryServiceImpl.java

查詢所有分類

package com.doudou.gulimall.product.service.impl;
​
​
import org.springframework.stereotype.Service;
​
import java.util.List;
import java.util.Map;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.doudou.common.utils.PageUtils;
import com.doudou.common.utils.Query;
​
import com.doudou.gulimall.product.dao.CategoryDao;
import com.doudou.gulimall.product.entity.CategoryEntity;
import com.doudou.gulimall.product.service.CategoryService;
​
​
@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {
//   @Autowired
//   CategoryDao categoryDao;
​
  @Override
  public PageUtils queryPage(Map<String, Object> params) {
    IPage<CategoryEntity> page = this.page(
        new Query<CategoryEntity>().getPage(params),
        new QueryWrapper<CategoryEntity>()
     );
​
    return new PageUtils(page);
   }
​
  @Override
  public List<CategoryEntity> listWithTree() {
    // 1.查出所有分類
    List<CategoryEntity> entities = baseMapper.selectList(null);//這裡寫null(沒有查詢條件，就是查詢所有)就是查詢所有的資料
​
​
    //2.組裝成父子的樹形結構
    return entities;
​
​
​
​
   }
​
}
​
 

獲取一級分類

CategoryServiceImpl .java

package com.doudou.gulimall.product.service.impl;
​
​
import org.springframework.stereotype.Service;
​
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
​
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.doudou.common.utils.PageUtils;
import com.doudou.common.utils.Query;
​
import com.doudou.gulimall.product.dao.CategoryDao;
import com.doudou.gulimall.product.entity.CategoryEntity;
import com.doudou.gulimall.product.service.CategoryService;
​
​
@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {
//   @Autowired
//   CategoryDao categoryDao;
​
  @Override
  public PageUtils queryPage(Map<String, Object> params) {
    IPage<CategoryEntity> page = this.page(
        new Query<CategoryEntity>().getPage(params),
        new QueryWrapper<CategoryEntity>()
     );
​
    return new PageUtils(page);
   }
​
  @Override
  public List<CategoryEntity> listWithTree() {
    // 1.查出所有分類
    List<CategoryEntity> entities = baseMapper.selectList(null);//這裡寫null(沒有查詢條件，就是查詢所有)就是查詢所有的資料
​
​
    //2.組裝成父子的樹形結構
​
    //2.1 找到所有的一級分類
    List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
    categoryEntity.getParentCid() == 0
​
     ).collect(Collectors.toList());
​
​
    return level1Menus;
​
​
​
​
   }
​
}
​
 

查詢子選單

CategoryServiceImpl.java

package com.doudou.gulimall.product.service.impl;
​
​
import org.springframework.stereotype.Service;
​
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
​
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.doudou.common.utils.PageUtils;
import com.doudou.common.utils.Query;
​
import com.doudou.gulimall.product.dao.CategoryDao;
import com.doudou.gulimall.product.entity.CategoryEntity;
import com.doudou.gulimall.product.service.CategoryService;
​
​
@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {
//   @Autowired
//   CategoryDao categoryDao;
​
  @Override
  public PageUtils queryPage(Map<String, Object> params) {
    IPage<CategoryEntity> page = this.page(
        new Query<CategoryEntity>().getPage(params),
        new QueryWrapper<CategoryEntity>()
     );
​
    return new PageUtils(page);
   }
​
  @Override
  public List<CategoryEntity> listWithTree() {
    // 1.查出所有分類
    List<CategoryEntity> entities = baseMapper.selectList(null);//這裡寫null(沒有查詢條件，就是查詢所有)就是查詢所有的資料
​
​
    //2.組裝成父子的樹形結構
​
    //2.1 找到所有的一級分類
    List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
    categoryEntity.getParentCid() == 0
​
     ).map((menu)->{
      menu.setChildren(getChildrens(menu, entities));
      return menu;
     }).sorted((menu1, menu2)->{
      return (menu1.getSort() == null ? 0 : menu1.getSort()) - (menu2.getSort() == null ? 0 : menu2.getSort());
     }).collect(Collectors.toList());
​
​
    return level1Menus;
​
   }
  //遞迴查詢所有選單的子選單
​
  private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all){
    List<CategoryEntity> childrean =all.stream().filter(categoryEntity -> {
      return categoryEntity.getParentCid() == root.getCatId();
     }).map(categoryEntity -> {
      //找到子選單
      categoryEntity.setChildren(getChildrens(categoryEntity, all));
      return categoryEntity;
     }).sorted((menu1, menu2)->{
      //2.選單排序
      return (menu1.getSort() == null ? 0 : menu1.getSort()) - (menu2.getSort() == null ? 0 : menu2.getSort());
     }).collect(Collectors.toList());
    return childrean;
​
   }
​
}
​
 

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