mybatis-puals+mysql

package com.example.mybatisplus.service.impl; import cn.hutool.core.bean.BeanUtil; import cn.hutool.core.collection.CollUtil; //import cn.hutool.core.util.StrUtil; //import com.baomidou.mybatisplus.core.metadata.OrderItem; import com.baomidou.mybatisplus.extension.plugins.pagination.Page; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import com.baomidou.mybatisplus.extension.toolkit.Db; import com.example.mybatisplus.domain.dto.PageDTO; import com.example.mybatisplus.domain.po.Address; import com.example.mybatisplus.domain.po.User; import com.example.mybatisplus.domain.query.UserQuery; import com.example.mybatisplus.domain.vo.AddressVO; import com.example.mybatisplus.domain.vo.UserVO; import com.example.mybatisplus.enums.UserStatus; import com.example.mybatisplus.mapper.UserMapper; import com.example.mybatisplus.service.IUserService; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import java.util.*; import java.util.stream.Collectors; @Service public class IUserServiceImpl extends ServiceImpl<UserMapper,User> implements IUserService { @Override @Transactional //抛出异常之后，事务会自动回滚，数据不会插入到数据库中(只能应用到 public 方法或者类上才有效) public void deductBalance(Long id, Double money) { // 1.查询用户 User user = this.getById(id); // 2.校验用户状态 if(user == null || user.getStatus() == UserStatus.FROZEN){ throw new RuntimeException("用户不存在或状态异常"); } // 3.校验余额 if(user.getBalance() < money){ throw new RuntimeException("余额不足"); } // 4.扣款 // baseMapper.deductBalance(id,money); double remainBalance = user.getBalance() - money; lambdaUpdate() .set(User::getBalance,remainBalance) .set(remainBalance == 0,User::getStatus,UserStatus.FROZEN) .eq(User::getId,id) .eq(User::getBalance,user.getBalance())//乐观锁 .update(); } /** * 根据多个条件查询用户 * @param minBalance maxBalance name status * @return List<User> */ @Override public List<User> queryUsers(Integer maxBalance, Integer minBalance, String name, Integer status) { return lambdaQuery() .like(name != null,User::getUsername,name) .le(maxBalance != null,User::getBalance,maxBalance)//小于等于 .ge(minBalance != null,User::getBalance,minBalance)//大于等于 .eq(status != null,User::getStatus,status)//等于 .list(); } @Override public UserVO getUserAndAddressById(Long id) { //1.查询用户 User user = this.getById(id); if(user == null || user.getStatus() == UserStatus.FROZEN){ throw new RuntimeException("用户不存在或状态异常"); } //2.查询用户地址 List<Address> addresses = Db.lambdaQuery(Address.class).eq(Address::getUserId, user.getId()).list(); // 3.封装VO // 3.1 转UserPO为VO UserVO userVO = BeanUtil.copyProperties(user, UserVO.class); // 3.2 转地址VO if(CollUtil.isNotEmpty(addresses)) { userVO.setAddresses(BeanUtil.copyToList(addresses, AddressVO.class)); } return userVO; } @Override public List<UserVO> getUserAndAddressByIds(List<Long> ids) { // 1.查询用户 List<User> users = listByIds(ids); if(CollUtil.isEmpty(users)){//用户不存在，换回空集合 return Collections.emptyList(); } // 2. 查询用户地址 // 2.1 获取已查询用户id List<Long> collect = users.stream().map(User::getId).collect(Collectors.toList()); // 2.2 查询用户地址 List<Address> addresses = Db.lambdaQuery(Address.class).in(Address::getUserId, collect).list(); // 2.3 转换成地址VO List<AddressVO> addressVOList = BeanUtil.copyToList(addresses, AddressVO.class); // 2.4 用户地址集合分组处理，相同用户放入一个集合（组）中 Map<Long, List<AddressVO>> listMap = new HashMap<>(0); if(CollUtil.isNotEmpty(addressVOList)){ listMap = addressVOList.stream().collect(Collectors.groupingBy(AddressVO::getUserId)); } // 3. 封装VO返回 List<UserVO> userVOS = new ArrayList<>(users.size()); for (User user : users) { // 3.1 转UserPO为VO UserVO userVO = BeanUtil.copyProperties(user, UserVO.class); // 3.2 获取用户地址 userVO.setAddresses(listMap.get(user.getId())); // 3.3 添加到集合中 userVOS.add(userVO); } return userVOS; } @Override//分页 public PageDTO<UserVO> queryUserPage(UserQuery userQuery) { String name = userQuery.getName(); Integer status = userQuery.getStatus(); // Integer pageNo = userQuery.getPageNo(); // Integer pageSize = userQuery.getPageSize(); // String sortBy = userQuery.getSortBy(); // Boolean isAsc = userQuery.getIsAsc(); // 1.构建查询条件 // Page<User> page = Page.of(pageNo, pageSize); // if(StrUtil.isNotBlank(sortBy) && isAsc != null) { // page.addOrder(new OrderItem().setAsc(isAsc).setColumn(sortBy)); // }else { // // 默认按照更新时间排序 // page.addOrder(new OrderItem().setAsc(false).setColumn("update_time")); // } Page<User> page = userQuery.toMpPageDefaultSortByUpdateTimeDesc(); // 2.分页查询 Page<User> userPage = lambdaQuery().like(name != null, User::getUsername, name) .eq(status != null, User::getStatus, status) .page(page); //3.封装VO // PageDTO<UserVO> dto = new PageDTO<>(); // dto.setTotal(userPage.getTotal());// 总条数 // dto.setPages(userPage.getPages());// 总页数 // List<User> records = userPage.getRecords();// 当前页数据 // if(CollUtil.isEmpty(records)){ // dto.setList(Collections.emptyList()); // return dto; // } // dto.setList(BeanUtil.copyToList(records, UserVO.class)); // // 4.返回 // return dto; // return PageDTO.of(userPage,UserVO.class); return PageDTO.of(userPage, user -> { //1.拷贝基础属性 UserVO userVO = BeanUtil.copyProperties(user, UserVO.class); //2.处理特殊逻辑（如隐藏名字后两位） userVO.setUsername(user.getUsername().substring(0, user.getUsername().length() - 2) + "**"); return userVO; }); }; }