MybatisPlus完整代码

package com.itheima.mp.service.impl; import cn.hutool.core.bean.BeanUtil; import cn.hutool.core.collection.CollUtil; 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.itheima.mp.domain.dto.PageDTO; import com.itheima.mp.domain.po.Address; import com.itheima.mp.domain.po.User; import com.itheima.mp.domain.query.UserQuery; import com.itheima.mp.domain.vo.AddressVO; import com.itheima.mp.domain.vo.UserVO; import com.itheima.mp.enums.UserStatus; import com.itheima.mp.mapper.UserMapper; import com.itheima.mp.service.IUserService; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import java.util.*; import java.util.stream.Collectors; @Service public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService { @Override @Transactional public void deductBalance(Long id, Integer money) { // 1.查询用户 User user = getById(id); // 2.校验用户状态 if (user == null || user.getStatus() == UserStatus.FROZEN) { throw new RuntimeException("用户状态异常！"); } // 3.校验余额是否充足 if (user.getBalance() < money) { throw new RuntimeException("用户余额不足！"); } // 4.扣减余额 update tb_user set balance = balance - ? int 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(); } @Override public List<User> queryUsers(String name, Integer status, Integer minBalance, Integer maxBalance) { return lambdaQuery() .like(name != null, User::getUsername, name) .eq(status != null, User::getStatus, status) .ge(minBalance != null, User::getBalance, minBalance) .le(maxBalance != null, User::getBalance, maxBalance) .list(); } @Override public UserVO queryUserAndAddressById(Long id) { // 1.查询用户 User user = getById(id); if (user == null || user.getStatus() == UserStatus.FROZEN) { throw new RuntimeException("用户状态异常！"); } // 2.查询地址 List<Address> addresses = Db.lambdaQuery(Address.class).eq(Address::getUserId, id).list(); // 3.封装VO // 3.1.转User的PO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> queryUserAndAddressByIds(List<Long> ids) { // 1.查询用户 List<User> users = listByIds(ids); if (CollUtil.isEmpty(users)) { return Collections.emptyList(); } // 2.查询地址 // 2.1.获取用户id集合 List<Long> userIds = users.stream().map(User::getId).collect(Collectors.toList()); // 2.2.根据用户id查询地址 List<Address> addresses = Db.lambdaQuery(Address.class).in(Address::getUserId, userIds).list(); // 2.3.转换地址VO List<AddressVO> addressVOList = BeanUtil.copyToList(addresses, AddressVO.class); // 2.4.用户地址集合分组处理，相同用户的放入一个集合（组）中 Map<Long, List<AddressVO>> addressMap = new HashMap<>(0); if(CollUtil.isNotEmpty(addressVOList)) { addressMap = addressVOList.stream().collect(Collectors.groupingBy(AddressVO::getUserId)); } // 3.转换VO返回 List<UserVO> list = new ArrayList<>(users.size()); for (User user : users) { // 3.1.转换User的PO为VO UserVO vo = BeanUtil.copyProperties(user, UserVO.class); list.add(vo); // 3.2.转换地址VO vo.setAddresses(addressMap.get(user.getId())); } return list; } @Override public PageDTO<UserVO> queryUsersPage(UserQuery query) { String name = query.getName(); Integer status = query.getStatus(); // 1.构建分页条件 Page<User> page = query.toMpPageDefaultSortByUpdateTime(); // 2.分页查询 Page<User> p = lambdaQuery() .like(name != null, User::getUsername, name) .eq(status != null, User::getStatus, status) .page(page); // 3.封装VO结果 return PageDTO.of(p,user -> { // 1.拷贝基础属性 UserVO vo = BeanUtil.copyProperties(user, UserVO.class); // 2.处理特殊逻辑 vo.setUsername(vo.getUsername().substring(0, vo.getUsername().length() - 2) + "**"); return vo; }); } }