myframe/application/src/main/java/com/ctsi/SysMenu/service/impl/SysMenuServiceImpl.java

package com.ctsi.SysMenu.service.impl;

import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.conditions.update.LambdaUpdateChainWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.ctsi.SysMenu.entity.SysMenu;
import com.ctsi.SysMenu.entity.SysMenuSearchPO;
import com.ctsi.SysMenu.mapper.SysMenuMapper;
import com.ctsi.SysMenu.service.SysMenuService;
import com.github.yulichang.wrapper.MPJLambdaWrapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.*;

/**
 * 菜单;(sys_menu)表服务实现类
 * @author : machaoyi
 * @date : 2024-1-10
 */
@Service
public class SysMenuServiceImpl implements SysMenuService{
    @Autowired
    private SysMenuMapper sysMenuMapper;

    /**
     * 通过ID查询单条数据
     *
     * @param id 主键
     * @return 实例对象
     */
    public SysMenu queryById(Long id){
        return sysMenuMapper.selectById(id);
    }

    /**
     * 分页查询
     *
     * @param sysMenu 筛选条件
     * @param current 当前页码
     * @param size  每页大小
     * @return
     */
    public Page<SysMenuSearchPO> paginQuery(SysMenu sysMenu, long current, long size){
        //1. 构建动态查询条件
        MPJLambdaWrapper<SysMenu> queryWrapper = new MPJLambdaWrapper<>();
        if(StrUtil.isNotBlank(sysMenu.getMenuTitle())){
            queryWrapper.eq(SysMenu::getMenuTitle, sysMenu.getMenuTitle());
        }
        if(StrUtil.isNotBlank(sysMenu.getMenuCode())){
            queryWrapper.eq(SysMenu::getMenuCode, sysMenu.getMenuCode());
        }
        if(StrUtil.isNotBlank(sysMenu.getMenuName())){
            queryWrapper.eq(SysMenu::getMenuName, sysMenu.getMenuName());
        }
        if(StrUtil.isNotBlank(sysMenu.getMenuIcon())){
            queryWrapper.eq(SysMenu::getMenuIcon, sysMenu.getMenuIcon());
        }
        queryWrapper.orderByAsc("ORDER_BY");
        //2. 执行分页查询
        Page<SysMenuSearchPO> pagin = new Page<>(current , size , true);
        IPage<SysMenuSearchPO> selectResult = sysMenuMapper.selectJoinPage(pagin , SysMenuSearchPO.class, queryWrapper);
        selectResult.setRecords(buildTree(selectResult.getRecords()));
        pagin.setPages(selectResult.getPages());
        pagin.setTotal(selectResult.getTotal());
        pagin.setRecords(selectResult.getRecords());
        //3. 返回结果
        return pagin;
    }

    /**
     * 新增数据
     *
     * @param sysMenu 实例对象
     * @return 实例对象
     */
    public SysMenu insert(SysMenu sysMenu){
        sysMenuMapper.insert(sysMenu);
        return sysMenu;
    }

    /**
     * 更新数据
     *
     * @param sysMenu 实例对象
     * @return 实例对象
     */
    public SysMenu update(SysMenu sysMenu){
        //1. 根据条件动态更新
        LambdaUpdateChainWrapper<SysMenu> chainWrapper = new LambdaUpdateChainWrapper<SysMenu>(sysMenuMapper);
        if(StrUtil.isNotBlank(sysMenu.getMenuTitle())){
            chainWrapper.set(SysMenu::getMenuTitle, sysMenu.getMenuTitle());
        }
        if(StrUtil.isNotBlank(sysMenu.getMenuCode())){
            chainWrapper.set(SysMenu::getMenuCode, sysMenu.getMenuCode());
        }
        if(StrUtil.isNotBlank(sysMenu.getMenuName())){
            chainWrapper.set(SysMenu::getMenuName, sysMenu.getMenuName());
        }
        if(StrUtil.isNotBlank(sysMenu.getMenuIcon())){
            chainWrapper.set(SysMenu::getMenuIcon, sysMenu.getMenuIcon());
        }
        //2. 设置主键，并更新
        chainWrapper.eq(SysMenu::getId, sysMenu.getId());
        boolean ret = chainWrapper.update();
        //3. 更新成功了，查询最最对象返回
        if(ret){
            return queryById(sysMenu.getId());
        }else{
            return sysMenu;
        }
    }

    /**
     * 通过主键删除数据
     *
     * @param id 主键
     * @return 是否成功
     */
    public boolean deleteById(Long id){
        int total = sysMenuMapper.deleteById(id);
        return total > 0;
    }
    public static List<SysMenuSearchPO> buildTree(List<SysMenuSearchPO> nodeList) {
        Map<Long, SysMenuSearchPO> nodeMap = new LinkedHashMap<>();

        // 将节点放入 Map 中，方便通过 id 查找
        for (SysMenuSearchPO node : nodeList) {
            nodeMap.put(node.getId(), node);
        }

        List<SysMenuSearchPO> tree = new ArrayList<>();

        // 逐个节点构建树
        for (SysMenuSearchPO node : nodeList) {
            if (node.getParentId() == 0) {
                // 根节点
                tree.add(buildTreeRecursively(node, nodeMap, node.getId()));
            }
        }

        return tree;
    }

    private static SysMenuSearchPO buildTreeRecursively(SysMenuSearchPO parentNode, Map<Long, SysMenuSearchPO> nodeMap, Long parentId) {
        List<SysMenuSearchPO> children = new ArrayList<>();

        // 查找当前节点的子节点
        nodeMap.forEach((id, node) -> {
            if (Objects.equals(node.getParentId(), parentId)) {
                children.add(buildTreeRecursively(node, nodeMap, node.getId()));
            }
        });
        // 将子节点设置到父节点
        parentNode.setChildren(children);

        return parentNode;
    }
}